18855979 has 2 divisors, whose sum is σ = 18855980. Its totient is φ = 18855978.

The previous prime is 18855953. The next prime is 18855983. The reversal of 18855979 is 97955881.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18855979 - 2¹¹ = 18853931 is a prime.

It is not a weakly prime, because it can be changed into another prime (18855919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9427989 + 9427990.

It is an arithmetic number, because the mean of its divisors is an integer number (9427990).

Almost surely, 2^18855979 is an apocalyptic number.

18855979 is a deficient number, since it is larger than the sum of its proper divisors (1).

18855979 is an equidigital number, since it uses as much as digits as its factorization.

18855979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 907200, while the sum is 52.

The square root of 18855979 is about 4342.3471763552. The cubic root of 18855979 is about 266.1642332874.

The spelling of 18855979 in words is "eighteen million, eight hundred fifty-five thousand, nine hundred seventy-nine".