31311988 has 12 divisors (see below), whose sum is σ = 55361572. Its totient is φ = 15494400.

The previous prime is 31311983. The next prime is 31311989. The reversal of 31311988 is 88911313.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18766224 + 12545764 = 4332^2 + 3542^2 .

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39963 + ... + 40738.

Almost surely, 2^31311988 is an apocalyptic number.

It is an amenable number.

31311988 is a deficient number, since it is larger than the sum of its proper divisors (24049584).

31311988 is a wasteful number, since it uses less digits than its factorization.

31311988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80802 (or 80800 counting only the distinct ones).

The product of its digits is 5184, while the sum is 34.

The square root of 31311988 is about 5595.7115722667. The cubic root of 31311988 is about 315.1883915477.

The spelling of 31311988 in words is "thirty-one million, three hundred eleven thousand, nine hundred eighty-eight".