30981888 has 216 divisors, whose sum is σ = 109051488. Its totient is φ = 8257536.

The previous prime is 30981877. The next prime is 30981911. The reversal of 30981888 is 88818903.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 274120 + ... + 274232.

It is an arithmetic number, because the mean of its divisors is an integer number (504868).

Almost surely, 2^30981888 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 30981888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54525744).

30981888 is an abundant number, since it is smaller than the sum of its proper divisors (78069600).

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

30981888 is a wasteful number, since it uses less digits than its factorization.

30981888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 45.

The square root of 30981888 is about 5566.1376195707. The cubic root of 30981888 is about 314.0768740878.

The spelling of 30981888 in words is "thirty million, nine hundred eighty-one thousand, eight hundred eighty-eight".