30981868 has 24 divisors (see below), whose sum is σ = 55062000. Its totient is φ = 15252288.

The previous prime is 30981859. The next prime is 30981869. The reversal of 30981868 is 86818903.

It is a happy number.

It is a super-2 number, since 2×30981868² = 1919752289538848, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (30981869) 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, 135178 + ... + 135406.

It is an arithmetic number, because the mean of its divisors is an integer number (2294250).

Almost surely, 2^30981868 is an apocalyptic number.

It is an amenable number.

30981868 is a deficient number, since it is larger than the sum of its proper divisors (24080132).

30981868 is a wasteful number, since it uses less digits than its factorization.

30981868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 609 (or 607 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 43.

The square root of 30981868 is about 5566.1358229925. The cubic root of 30981868 is about 314.0768065049.

The spelling of 30981868 in words is "thirty million, nine hundred eighty-one thousand, eight hundred sixty-eight".