31297392 has 120 divisors (see below), whose sum is σ = 101942880. Its totient is φ = 8778240.

The previous prime is 31297373. The next prime is 31297397. The reversal of 31297392 is 29379213.

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31297397) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61234 + ... + 61742.

It is an arithmetic number, because the mean of its divisors is an integer number (849524).

Almost surely, 2^31297392 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 31297392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50971440).

31297392 is an abundant number, since it is smaller than the sum of its proper divisors (70645488).

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

31297392 is a wasteful number, since it uses less digits than its factorization.

31297392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 591 (or 582 counting only the distinct ones).

The product of its digits is 20412, while the sum is 36.

The square root of 31297392 is about 5594.4072072026. The cubic root of 31297392 is about 315.1394091922.

The spelling of 31297392 in words is "thirty-one million, two hundred ninety-seven thousand, three hundred ninety-two".