30891868 has 12 divisors (see below), whose sum is σ = 61783792. Its totient is φ = 13239360.

The previous prime is 30891857. The next prime is 30891893. The reversal of 30891868 is 86819803.

It is a happy number.

30891868 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 551613 + ... + 551668.

Almost surely, 2^30891868 is an apocalyptic number.

It is an amenable number.

30891868 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

30891868 is a wasteful number, since it uses less digits than its factorization.

30891868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1103292 (or 1103290 counting only the distinct ones).

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

The square root of 30891868 is about 5558.0453398654. The cubic root of 30891868 is about 313.7723883645.

The spelling of 30891868 in words is "thirty million, eight hundred ninety-one thousand, eight hundred sixty-eight".