31392 has 36 divisors (see below), whose sum is σ = 90090. Its totient is φ = 10368.

The previous prime is 31391. The next prime is 31393. The reversal of 31392 is 29313.

It is an interprime number because it is at equal distance from previous prime (31391) and next prime (31393).

It can be written as a sum of positive squares in only one way, i.e., 24336 + 7056 = 156^2 + 84^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a nude number because it is divisible by every one of its digits.

It is a plaindrome in base 13.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 31392.

It is not an unprimeable number, because it can be changed into a prime (31391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 234 + ... + 342.

2³¹³⁹² is an apocalyptic number.

31392 is a gapful number since it is divisible by the number (32) 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 31392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45045).

31392 is an abundant number, since it is smaller than the sum of its proper divisors (58698).

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

31392 is a wasteful number, since it uses less digits than its factorization.

31392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125 (or 114 counting only the distinct ones).

The product of its digits is 162, while the sum is 18.

The square root of 31392 is about 177.1778767228. The cubic root of 31392 is about 31.5456631764.

The spelling of 31392 in words is "thirty-one thousand, three hundred ninety-two".