18668920 has 16 divisors (see below), whose sum is σ = 42005160. Its totient is φ = 7467552.

The previous prime is 18668861. The next prime is 18668921. The reversal of 18668920 is 2986681.

It is a Harshad number since it is a multiple of its sum of digits (40), and also a Moran number because the ratio is a prime number: 466723 = 18668920 / (1 + 8 + 6 + 6 + 8 + 9 + 2 + 0).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18668921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 233322 + ... + 233401.

Almost surely, 2^18668920 is an apocalyptic number.

18668920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18668920 is an abundant number, since it is smaller than the sum of its proper divisors (23336240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18668920 is a wasteful number, since it uses less digits than its factorization.

18668920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466734 (or 466730 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 18668920 is about 4320.7545637307. The cubic root of 18668920 is about 265.2811540758.

The spelling of 18668920 in words is "eighteen million, six hundred sixty-eight thousand, nine hundred twenty".