18973994 has 16 divisors (see below), whose sum is σ = 31304448. Its totient is φ = 8570352.

The previous prime is 18973979. The next prime is 18974009. The reversal of 18973994 is 49937981.

It is an interprime number because it is at equal distance from previous prime (18973979) and next prime (18974009).

It is a Curzon number.

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, 6542 + ... + 8985.

It is an arithmetic number, because the mean of its divisors is an integer number (1956528).

Almost surely, 2^18973994 is an apocalyptic number.

18973994 is a deficient number, since it is larger than the sum of its proper divisors (12330454).

18973994 is a wasteful number, since it uses less digits than its factorization.

18973994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15589.

The product of its digits is 489888, while the sum is 50.

The square root of 18973994 is about 4355.9148292867. The cubic root of 18973994 is about 266.7183646296.

The spelling of 18973994 in words is "eighteen million, nine hundred seventy-three thousand, nine hundred ninety-four".