18018979 has 4 divisors (see below), whose sum is σ = 19657080. Its totient is φ = 16380880.

The previous prime is 18018971. The next prime is 18018983. The reversal of 18018979 is 97981081.

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 18018979 - 2³ = 18018971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18018971) 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, 819034 + ... + 819055.

It is an arithmetic number, because the mean of its divisors is an integer number (4914270).

Almost surely, 2^18018979 is an apocalyptic number.

18018979 is a deficient number, since it is larger than the sum of its proper divisors (1638101).

18018979 is a wasteful number, since it uses less digits than its factorization.

18018979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1638100.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 18018979 is about 4244.8767944429. The cubic root of 18018979 is about 262.1662164204.

The spelling of 18018979 in words is "eighteen million, eighteen thousand, nine hundred seventy-nine".