18278056538 has 48 divisors (see below), whose sum is σ = 32558493024. Its totient is φ = 7671454560.

The previous prime is 18278056441. The next prime is 18278056579. The reversal of 18278056538 is 83565087281.

It is a self number, because there is not a number n which added to its sum of digits gives 18278056538.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1127873 + ... + 1143963.

It is an arithmetic number, because the mean of its divisors is an integer number (678301938).

Almost surely, 2^18278056538 is an apocalyptic number.

18278056538 is a deficient number, since it is larger than the sum of its proper divisors (14280436486).

18278056538 is a wasteful number, since it uses less digits than its factorization.

18278056538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16347 (or 16340 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 53.

The spelling of 18278056538 in words is "eighteen billion, two hundred seventy-eight million, fifty-six thousand, five hundred thirty-eight".