18939964 has 6 divisors (see below), whose sum is σ = 33144944. Its totient is φ = 9469980.

The previous prime is 18939959. The next prime is 18939983. The reversal of 18939964 is 46993981.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2367492 + ... + 2367499.

Almost surely, 2^18939964 is an apocalyptic number.

It is an amenable number.

18939964 is a deficient number, since it is larger than the sum of its proper divisors (14204980).

18939964 is a wasteful number, since it uses less digits than its factorization.

18939964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4734995 (or 4734993 counting only the distinct ones).

The product of its digits is 419904, while the sum is 49.

The square root of 18939964 is about 4352.0068933769. The cubic root of 18939964 is about 266.5588154141.

The spelling of 18939964 in words is "eighteen million, nine hundred thirty-nine thousand, nine hundred sixty-four".