31020000 has 240 divisors, whose sum is σ = 113363712. Its totient is φ = 7360000.

The previous prime is 31019993. The next prime is 31020001. The reversal of 31020000 is 2013.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31020001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 659977 + ... + 660023.

Almost surely, 2^31020000 is an apocalyptic number.

31020000 is a gapful number since it is divisible by the number (30) 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 31020000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56681856).

31020000 is an abundant number, since it is smaller than the sum of its proper divisors (82343712).

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

31020000 is a wasteful number, since it uses less digits than its factorization.

31020000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91 (or 68 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 6.

The square root of 31020000 is about 5569.5601262577. The cubic root of 31020000 is about 314.2056072892.

Adding to 31020000 its reverse (2013), we get a palindrome (31022013).

The spelling of 31020000 in words is "thirty-one million, twenty thousand".