31201988 has 12 divisors (see below), whose sum is σ = 55499052. Its totient is φ = 15345120.

The previous prime is 31201981. The next prime is 31201991. The reversal of 31201988 is 88910213.

It can be written as a sum of positive squares in 2 ways, for example, as 643204 + 30558784 = 802^2 + 5528^2 .

It is not an unprimeable number, because it can be changed into a prime (31201981) 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, 63695 + ... + 64182.

It is an arithmetic number, because the mean of its divisors is an integer number (4624921).

Almost surely, 2^31201988 is an apocalyptic number.

It is an amenable number.

31201988 is a deficient number, since it is larger than the sum of its proper divisors (24297064).

31201988 is a wasteful number, since it uses less digits than its factorization.

31201988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127942 (or 127940 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 31201988 is about 5585.8739692191. The cubic root of 31201988 is about 314.8188695798.

The spelling of 31201988 in words is "thirty-one million, two hundred one thousand, nine hundred eighty-eight".