18422720 has 28 divisors (see below), whose sum is σ = 43869864. Its totient is φ = 7368960.

The previous prime is 18422693. The next prime is 18422737. The reversal of 18422720 is 2722481.

It is a super-2 number, since 2×18422720² = 678793224396800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18422720.

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, 28466 + ... + 29105.

Almost surely, 2^18422720 is an apocalyptic number.

18422720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18422720 is an abundant number, since it is smaller than the sum of its proper divisors (25447144).

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

18422720 is an equidigital number, since it uses as much as digits as its factorization.

18422720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57588 (or 57578 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 18422720 is about 4292.1696145423. The cubic root of 18422720 is about 264.1098410390.

The spelling of 18422720 in words is "eighteen million, four hundred twenty-two thousand, seven hundred twenty".