18320979 has 4 divisors (see below), whose sum is σ = 24427976. Its totient is φ = 12213984.

The previous prime is 18320977. The next prime is 18320983. The reversal of 18320979 is 97902381.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 18320979 - 2¹ = 18320977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18320971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3053494 + ... + 3053499.

It is an arithmetic number, because the mean of its divisors is an integer number (6106994).

Almost surely, 2^18320979 is an apocalyptic number.

18320979 is a deficient number, since it is larger than the sum of its proper divisors (6106997).

18320979 is an equidigital number, since it uses as much as digits as its factorization.

18320979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6106996.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 18320979 is about 4280.3012744432. The cubic root of 18320979 is about 263.6227537708.

The spelling of 18320979 in words is "eighteen million, three hundred twenty thousand, nine hundred seventy-nine".