18997579 has 4 divisors (see below), whose sum is σ = 19102720. Its totient is φ = 18892440.

The previous prime is 18997571. The next prime is 18997603. The reversal of 18997579 is 97579981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97579981 = 1801 ⋅54181.

It is a cyclic number.

It is not a de Polignac number, because 18997579 - 2³ = 18997571 is a prime.

It is a super-2 number, since 2×18997579² = 721816015722482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18997571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52299 + ... + 52660.

It is an arithmetic number, because the mean of its divisors is an integer number (4775680).

Almost surely, 2^18997579 is an apocalyptic number.

18997579 is a deficient number, since it is larger than the sum of its proper divisors (105141).

18997579 is a wasteful number, since it uses less digits than its factorization.

18997579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105140.

The product of its digits is 1428840, while the sum is 55.

The square root of 18997579 is about 4358.6212269478. The cubic root of 18997579 is about 266.8288307059.

The spelling of 18997579 in words is "eighteen million, nine hundred ninety-seven thousand, five hundred seventy-nine".