18662720 has 28 divisors (see below), whose sum is σ = 44441364. Its totient is φ = 7464960.

The previous prime is 18662717. The next prime is 18662771. The reversal of 18662720 is 2726681.

It can be written as a sum of positive squares in 2 ways, for example, as 2534464 + 16128256 = 1592^2 + 4016^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

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, 28841 + ... + 29480.

Almost surely, 2^18662720 is an apocalyptic number.

18662720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18662720 is an abundant number, since it is smaller than the sum of its proper divisors (25778644).

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

18662720 is an equidigital number, since it uses as much as digits as its factorization.

18662720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58338 (or 58328 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 18662720 is about 4320.0370368783. The cubic root of 18662720 is about 265.2517839558.

The spelling of 18662720 in words is "eighteen million, six hundred sixty-two thousand, seven hundred twenty".