31031312 has 40 divisors (see below), whose sum is σ = 65167704. Its totient is φ = 14229504.

The previous prime is 31031311. The next prime is 31031317. The reversal of 31031312 is 21313013.

It can be written as a sum of positive squares in 4 ways, for example, as 1263376 + 29767936 = 1124^2 + 5456^2 .

It is not an unprimeable number, because it can be changed into a prime (31031311) 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, 39758 + ... + 40530.

Almost surely, 2^31031312 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 31031312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32583852).

31031312 is an abundant number, since it is smaller than the sum of its proper divisors (34136392).

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

31031312 is a wasteful number, since it uses less digits than its factorization.

31031312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 987 (or 981 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 31031312 is about 5570.5755537467. The cubic root of 31031312 is about 314.2437962197.

Adding to 31031312 its reverse (21313013), we get a palindrome (52344325).

The spelling of 31031312 in words is "thirty-one million, thirty-one thousand, three hundred twelve".