18665916 has 24 divisors (see below), whose sum is σ = 43688400. Its totient is φ = 6202752.

The previous prime is 18665897. The next prime is 18665921. The reversal of 18665916 is 61956681.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1960 + ... + 6416.

It is an arithmetic number, because the mean of its divisors is an integer number (1820350).

Almost surely, 2^18665916 is an apocalyptic number.

It is an amenable number.

18665916 is an abundant number, since it is smaller than the sum of its proper divisors (25022484).

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

18665916 is a wasteful number, since it uses less digits than its factorization.

18665916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4813 (or 4811 counting only the distinct ones).

The product of its digits is 77760, while the sum is 42.

The square root of 18665916 is about 4320.4069252791. The cubic root of 18665916 is about 265.2669245911.

The spelling of 18665916 in words is "eighteen million, six hundred sixty-five thousand, nine hundred sixteen".