18138579 has 4 divisors (see below), whose sum is σ = 24184776. Its totient is φ = 12092384.

The previous prime is 18138563. The next prime is 18138587. The reversal of 18138579 is 97583181.

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

It is a cyclic number.

It is not a de Polignac number, because 18138579 - 2⁴ = 18138563 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18138579.

It is not an unprimeable number, because it can be changed into a prime (18138509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3023094 + ... + 3023099.

It is an arithmetic number, because the mean of its divisors is an integer number (6046194).

Almost surely, 2^18138579 is an apocalyptic number.

18138579 is a deficient number, since it is larger than the sum of its proper divisors (6046197).

18138579 is an equidigital number, since it uses as much as digits as its factorization.

18138579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6046196.

The product of its digits is 60480, while the sum is 42.

The square root of 18138579 is about 4258.9410655702. The cubic root of 18138579 is about 262.7449758425.

The spelling of 18138579 in words is "eighteen million, one hundred thirty-eight thousand, five hundred seventy-nine".