18909964 has 12 divisors (see below), whose sum is σ = 33146064. Its totient is φ = 9439664.

The previous prime is 18909949. The next prime is 18909983. The reversal of 18909964 is 46990981.

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, 784 + ... + 6199.

It is an arithmetic number, because the mean of its divisors is an integer number (2762172).

Almost surely, 2^18909964 is an apocalyptic number.

It is an amenable number.

18909964 is a deficient number, since it is larger than the sum of its proper divisors (14236100).

18909964 is a wasteful number, since it uses less digits than its factorization.

18909964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7664 (or 7662 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 46.

The square root of 18909964 is about 4348.5588417314. The cubic root of 18909964 is about 266.4180022223.

The spelling of 18909964 in words is "eighteen million, nine hundred nine thousand, nine hundred sixty-four".