18973329778 has 16 divisors (see below), whose sum is σ = 30741834816. Its totient is φ = 8730461520.

The previous prime is 18973329769. The next prime is 18973329797. The reversal of 18973329778 is 87792337981.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1093726 + ... + 1110937.

It is an arithmetic number, because the mean of its divisors is an integer number (1921364676).

Almost surely, 2^18973329778 is an apocalyptic number.

18973329778 is a deficient number, since it is larger than the sum of its proper divisors (11768505038).

18973329778 is a wasteful number, since it uses less digits than its factorization.

18973329778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2205009.

The product of its digits is 32006016, while the sum is 64.

The spelling of 18973329778 in words is "eighteen billion, nine hundred seventy-three million, three hundred twenty-nine thousand, seven hundred seventy-eight".