18931868 has 12 divisors (see below), whose sum is σ = 33901560. Its totient is φ = 9245712.

The previous prime is 18931859. The next prime is 18931877. The reversal of 18931868 is 86813981.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18931859) and next prime (18931877).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54863 + ... + 55206.

It is an arithmetic number, because the mean of its divisors is an integer number (2825130).

Almost surely, 2^18931868 is an apocalyptic number.

It is an amenable number.

18931868 is a deficient number, since it is larger than the sum of its proper divisors (14969692).

18931868 is a wasteful number, since it uses less digits than its factorization.

18931868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110116 (or 110114 counting only the distinct ones).

The product of its digits is 82944, while the sum is 44.

The square root of 18931868 is about 4351.0766483711. The cubic root of 18931868 is about 266.5208292853.

The spelling of 18931868 in words is "eighteen million, nine hundred thirty-one thousand, eight hundred sixty-eight".