18661518453634 has 16 divisors (see below), whose sum is σ = 32771447041536. Its totient is φ = 7802725485600.

The previous prime is 18661518453601. The next prime is 18661518453653. The reversal of 18661518453634 is 43635481516681.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16255677522 + ... + 16255678669.

It is an arithmetic number, because the mean of its divisors is an integer number (2048215440096).

Almost surely, 2^{18661518453634} is an apocalyptic number.

18661518453634 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

18661518453634 is a deficient number, since it is larger than the sum of its proper divisors (14109928587902).

18661518453634 is a wasteful number, since it uses less digits than its factorization.

18661518453634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32511356241.

The product of its digits is 49766400, while the sum is 61.

The spelling of 18661518453634 in words is "eighteen trillion, six hundred sixty-one billion, five hundred eighteen million, four hundred fifty-three thousand, six hundred thirty-four".