18397568242 has 4 divisors (see below), whose sum is σ = 27596352366. Its totient is φ = 9198784120.

The previous prime is 18397568179. The next prime is 18397568291. The reversal of 18397568242 is 24286579381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24286579381 = 3257 ⋅7456733.

It can be written as a sum of positive squares in only one way, i.e., 18268495921 + 129072321 = 135161^2 + 11361^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4599392059 + ... + 4599392062.

Almost surely, 2^18397568242 is an apocalyptic number.

18397568242 is a deficient number, since it is larger than the sum of its proper divisors (9198784124).

18397568242 is an equidigital number, since it uses as much as digits as its factorization.

18397568242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9198784123.

The product of its digits is 5806080, while the sum is 55.

The spelling of 18397568242 in words is "eighteen billion, three hundred ninety-seven million, five hundred sixty-eight thousand, two hundred forty-two".