31712320 has 56 divisors (see below), whose sum is σ = 76270104. Its totient is φ = 12558336.

The previous prime is 31712309. The next prime is 31712321. The reversal of 31712320 is 2321713.

It can be written as a sum of positive squares in 4 ways, for example, as 1065024 + 30647296 = 1032^2 + 5536^2 .

It is not an unprimeable number, because it can be changed into a prime (31712321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35722 + ... + 36598.

Almost surely, 2^31712320 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 31712320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38135052).

31712320 is an abundant number, since it is smaller than the sum of its proper divisors (44557784).

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

31712320 is a wasteful number, since it uses less digits than its factorization.

31712320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1007 (or 997 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 19.

The square root of 31712320 is about 5631.3692828654. The cubic root of 31712320 is about 316.5259627291.

The spelling of 31712320 in words is "thirty-one million, seven hundred twelve thousand, three hundred twenty".