31248981 has 12 divisors (see below), whose sum is σ = 45285708. Its totient is φ = 20764224.

The previous prime is 31248953. The next prime is 31248983. The reversal of 31248981 is 18984213.

It can be written as a sum of positive squares in 2 ways, for example, as 10400625 + 20848356 = 3225^2 + 4566^2 .

It is not a de Polignac number, because 31248981 - 2¹¹ = 31246933 is a prime.

It is a super-2 number, since 2×31248981² = 1952997627076722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31248983) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2730 + ... + 8363.

It is an arithmetic number, because the mean of its divisors is an integer number (3773809).

Almost surely, 2^31248981 is an apocalyptic number.

It is an amenable number.

31248981 is a deficient number, since it is larger than the sum of its proper divisors (14036727).

31248981 is a wasteful number, since it uses less digits than its factorization.

31248981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11412 (or 11409 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 31248981 is about 5590.0788008757. The cubic root of 31248981 is about 314.9768388110.

The spelling of 31248981 in words is "thirty-one million, two hundred forty-eight thousand, nine hundred eighty-one".