18979 has 2 divisors, whose sum is σ = 18980. Its totient is φ = 18978.

The previous prime is 18973. The next prime is 19001. The reversal of 18979 is 97981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18979 - 2⁵ = 18947 is a prime.

18979 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (18973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9489 + 9490.

It is an arithmetic number, because the mean of its divisors is an integer number (9490).

2¹⁸⁹⁷⁹ is an apocalyptic number.

18979 is a deficient number, since it is larger than the sum of its proper divisors (1).

18979 is an equidigital number, since it uses as much as digits as its factorization.

18979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 34.

The square root of 18979 is about 137.7642914546. The cubic root of 18979 is about 26.6741819096.

The spelling of 18979 in words is "eighteen thousand, nine hundred seventy-nine".