30961872 has 40 divisors (see below), whose sum is σ = 88873280. Its totient is φ = 10320480.

The previous prime is 30961867. The next prime is 30961877. The reversal of 30961872 is 27816903.

30961872 is a `hidden beast` number, since 30 + 9 + 618 + 7 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (30961867) and next prime (30961877).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30961877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35404 + ... + 36267.

It is an arithmetic number, because the mean of its divisors is an integer number (2221832).

Almost surely, 2^30961872 is an apocalyptic number.

It is an amenable number.

30961872 is an abundant number, since it is smaller than the sum of its proper divisors (57911408).

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

30961872 is a wasteful number, since it uses less digits than its factorization.

30961872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71688 (or 71676 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 30961872 is about 5564.3393138808. The cubic root of 30961872 is about 314.0092225509.

The spelling of 30961872 in words is "thirty million, nine hundred sixty-one thousand, eight hundred seventy-two".