30861972 has 36 divisors (see below), whose sum is σ = 80904096. Its totient is φ = 10287000.

The previous prime is 30861967. The next prime is 30861997. The reversal of 30861972 is 27916803.

30861972 is a `hidden beast` number, since 30 + 8 + 619 + 7 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×30861972² = 1904922631457568, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14904 + ... + 16847.

It is an arithmetic number, because the mean of its divisors is an integer number (2247336).

Almost surely, 2^30861972 is an apocalyptic number.

It is an amenable number.

30861972 is an abundant number, since it is smaller than the sum of its proper divisors (50042124).

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

30861972 is a wasteful number, since it uses less digits than its factorization.

30861972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31770 (or 31756 counting only the distinct ones).

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

The square root of 30861972 is about 5555.3552541669. The cubic root of 30861972 is about 313.6711366154.

The spelling of 30861972 in words is "thirty million, eight hundred sixty-one thousand, nine hundred seventy-two".