78312 has 32 divisors (see below), whose sum is σ = 211680. Its totient is φ = 24000.

The previous prime is 78311. The next prime is 78317. The reversal of 78312 is 21387.

It is a super-2 number, since 2×78312² = 12265538688, which contains 22 as substring.

It is a Smith number, since the sum of its digits (21) coincides with the sum of the digits of its prime factors.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 78312.

It is not an unprimeable number, because it can be changed into a prime (78311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187 + ... + 437.

It is an arithmetic number, because the mean of its divisors is an integer number (6615).

2⁷⁸³¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105840).

78312 is an abundant number, since it is smaller than the sum of its proper divisors (133368).

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

78312 is a wasteful number, since it uses less digits than its factorization.

78312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273 (or 269 counting only the distinct ones).

The product of its digits is 336, while the sum is 21.

The square root of 78312 is about 279.8428130219. The cubic root of 78312 is about 42.7834798094.

Adding to 78312 its reverse (21387), we get a palindrome (99699).

It can be divided in two parts, 78 and 312, that multiplied together give a square (24336 = 156²).

The spelling of 78312 in words is "seventy-eight thousand, three hundred twelve".