18931916 has 6 divisors (see below), whose sum is σ = 33130860. Its totient is φ = 9465956.

The previous prime is 18931903. The next prime is 18931919. The reversal of 18931916 is 61913981.

It is a self number, because there is not a number n which added to its sum of digits gives 18931916.

It is not an unprimeable number, because it can be changed into a prime (18931919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2366486 + ... + 2366493.

It is an arithmetic number, because the mean of its divisors is an integer number (5521810).

Almost surely, 2^18931916 is an apocalyptic number.

It is an amenable number.

18931916 is a deficient number, since it is larger than the sum of its proper divisors (14198944).

18931916 is a wasteful number, since it uses less digits than its factorization.

18931916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4732983 (or 4732981 counting only the distinct ones).

The product of its digits is 11664, while the sum is 38.

The square root of 18931916 is about 4351.0821642437. The cubic root of 18931916 is about 266.5210545314.

The spelling of 18931916 in words is "eighteen million, nine hundred thirty-one thousand, nine hundred sixteen".