18874747538 has 4 divisors (see below), whose sum is σ = 28312121310. Its totient is φ = 9437373768.

The previous prime is 18874747517. The next prime is 18874747559. The reversal of 18874747538 is 83574747881.

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

It is an interprime number because it is at equal distance from previous prime (18874747517) and next prime (18874747559).

It can be written as a sum of positive squares in only one way, i.e., 17521022689 + 1353724849 = 132367^2 + 36793^2 .

It is a super-2 number, since 2×18874747538² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4718686883 + ... + 4718686886.

Almost surely, 2^18874747538 is an apocalyptic number.

18874747538 is a deficient number, since it is larger than the sum of its proper divisors (9437373772).

18874747538 is an equidigital number, since it uses as much as digits as its factorization.

18874747538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9437373771.

The product of its digits is 42147840, while the sum is 62.

The spelling of 18874747538 in words is "eighteen billion, eight hundred seventy-four million, seven hundred forty-seven thousand, five hundred thirty-eight".