18390639946 has 8 divisors (see below), whose sum is σ = 31526811360. Its totient is φ = 7881702828.

The previous prime is 18390639931. The next prime is 18390639979. The reversal of 18390639946 is 64993609381.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 656808556 + ... + 656808583.

It is an arithmetic number, because the mean of its divisors is an integer number (3940851420).

Almost surely, 2^18390639946 is an apocalyptic number.

18390639946 is a deficient number, since it is larger than the sum of its proper divisors (13136171414).

18390639946 is a wasteful number, since it uses less digits than its factorization.

18390639946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1313617148.

The product of its (nonzero) digits is 7558272, while the sum is 58.

The spelling of 18390639946 in words is "eighteen billion, three hundred ninety million, six hundred thirty-nine thousand, nine hundred forty-six".