87120 has 90 divisors (see below), whose sum is σ = 321594. Its totient is φ = 21120.

The previous prime is 87119. The next prime is 87121. The reversal of 87120 is 2178.

It is an interprime number because it is at equal distance from previous prime (87119) and next prime (87121).

It can be written as a sum of positive squares in only one way, i.e., 69696 + 17424 = 264^2 + 132^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 87093 and 87102.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 87120.

It is not an unprimeable number, because it can be changed into a prime (87121) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 7915 + ... + 7925.

2⁸⁷¹²⁰ is an apocalyptic number.

87120 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 87120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160797).

87120 is an abundant number, since it is smaller than the sum of its proper divisors (234474).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87120 is a wasteful number, since it uses less digits than its factorization.

87120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 87120 is about 295.1609730300. The cubic root of 87120 is about 44.3308394901.

Adding to 87120 its reverse (2178), we get a palindrome (89298).

It can be divided in two parts, 87 and 120, that multiplied together give a triangular number (10440 = T₁₄₄).

The spelling of 87120 in words is "eighty-seven thousand, one hundred twenty".