18668516 has 24 divisors (see below), whose sum is σ = 34750296. Its totient is φ = 8744960.

The previous prime is 18668513. The next prime is 18668549. The reversal of 18668516 is 61586681.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11356900 + 7311616 = 3370^2 + 2704^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18668513) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18620 + ... + 19596.

It is an arithmetic number, because the mean of its divisors is an integer number (1447929).

Almost surely, 2^18668516 is an apocalyptic number.

It is an amenable number.

18668516 is a deficient number, since it is larger than the sum of its proper divisors (16081780).

18668516 is a wasteful number, since it uses less digits than its factorization.

18668516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1279 (or 1277 counting only the distinct ones).

The product of its digits is 69120, while the sum is 41.

The square root of 18668516 is about 4320.7078123844. The cubic root of 18668516 is about 265.2792404790.

The spelling of 18668516 in words is "eighteen million, six hundred sixty-eight thousand, five hundred sixteen".