18336878242 has 4 divisors (see below), whose sum is σ = 27505317366. Its totient is φ = 9168439120.

The previous prime is 18336878233. The next prime is 18336878243. The reversal of 18336878242 is 24287863381.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 18330722881 + 6155361 = 135391^2 + 2481^2 .

It is a super-2 number, since 2×18336878242² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18336878242.

It is not an unprimeable number, because it can be changed into a prime (18336878243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4584219559 + ... + 4584219562.

Almost surely, 2^18336878242 is an apocalyptic number.

18336878242 is a deficient number, since it is larger than the sum of its proper divisors (9168439124).

18336878242 is an equidigital number, since it uses as much as digits as its factorization.

18336878242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9168439123.

The product of its digits is 3096576, while the sum is 52.

The spelling of 18336878242 in words is "eighteen billion, three hundred thirty-six million, eight hundred seventy-eight thousand, two hundred forty-two".