18638620911 has 40 divisors (see below), whose sum is σ = 28394615040. Its totient is φ = 12180711312.

The previous prime is 18638620879. The next prime is 18638620937. The reversal of 18638620911 is 11902683681.

18638620911 is a `hidden beast` number, since 1 + 8 + 6 + 3 + 8 + 620 + 9 + 11 = 666.

It is not a de Polignac number, because 18638620911 - 2⁵ = 18638620879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18638620111) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1748580 + ... + 1759206.

It is an arithmetic number, because the mean of its divisors is an integer number (709865376).

Almost surely, 2^18638620911 is an apocalyptic number.

18638620911 is a deficient number, since it is larger than the sum of its proper divisors (9755994129).

18638620911 is a wasteful number, since it uses less digits than its factorization.

18638620911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11065 (or 11056 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The spelling of 18638620911 in words is "eighteen billion, six hundred thirty-eight million, six hundred twenty thousand, nine hundred eleven".