18973665 has 24 divisors (see below), whose sum is σ = 33591168. Its totient is φ = 9902880.

The previous prime is 18973657. The next prime is 18973709. The reversal of 18973665 is 56637981.

It is a happy number.

It is not a de Polignac number, because 18973665 - 2³ = 18973657 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18973665.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2371 + ... + 6600.

It is an arithmetic number, because the mean of its divisors is an integer number (1399632).

Almost surely, 2^18973665 is an apocalyptic number.

18973665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18973665 is a deficient number, since it is larger than the sum of its proper divisors (14617503).

18973665 is a wasteful number, since it uses less digits than its factorization.

18973665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9029 (or 9026 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 18973665 is about 4355.8770643809. The cubic root of 18973665 is about 266.7168230310.

The spelling of 18973665 in words is "eighteen million, nine hundred seventy-three thousand, six hundred sixty-five".