18856558979 has 2 divisors, whose sum is σ = 18856558980. Its totient is φ = 18856558978.

The previous prime is 18856558957. The next prime is 18856558991. The reversal of 18856558979 is 97985565881.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18856558979 - 2²⁰ = 18855510403 is a prime.

It is not a weakly prime, because it can be changed into another prime (18856558999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9428279489 + 9428279490.

It is an arithmetic number, because the mean of its divisors is an integer number (9428279490).

Almost surely, 2^18856558979 is an apocalyptic number.

18856558979 is a deficient number, since it is larger than the sum of its proper divisors (1).

18856558979 is an equidigital number, since it uses as much as digits as its factorization.

18856558979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728000, while the sum is 71.

The spelling of 18856558979 in words is "eighteen billion, eight hundred fifty-six million, five hundred fifty-eight thousand, nine hundred seventy-nine".