18408918566956 has 6 divisors (see below), whose sum is σ = 32215607492180. Its totient is φ = 9204459283476.

The previous prime is 18408918566933. The next prime is 18408918566959. The reversal of 18408918566956 is 65966581980481.

It is not an unprimeable number, because it can be changed into a prime (18408918566959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2301114820866 + ... + 2301114820873.

Almost surely, 2^{18408918566956} is an apocalyptic number.

It is an amenable number.

18408918566956 is a deficient number, since it is larger than the sum of its proper divisors (13806688925224).

18408918566956 is a wasteful number, since it uses less digits than its factorization.

18408918566956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4602229641743 (or 4602229641741 counting only the distinct ones).

The product of its (nonzero) digits is 895795200, while the sum is 76.

The spelling of 18408918566956 in words is "eighteen trillion, four hundred eight billion, nine hundred eighteen million, five hundred sixty-six thousand, nine hundred fifty-six".