18722520 has 96 divisors (see below), whose sum is σ = 61467120. Its totient is φ = 4942080.

The previous prime is 18722513. The next prime is 18722549. The reversal of 18722520 is 2522781.

It is a congruent number.

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, 46962 + ... + 47358.

Almost surely, 2^18722520 is an apocalyptic number.

18722520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18722520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30733560).

18722520 is an abundant number, since it is smaller than the sum of its proper divisors (42744600).

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

18722520 is a wasteful number, since it uses less digits than its factorization.

18722520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 545 (or 538 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 18722520 is about 4326.9527383599. The cubic root of 18722520 is about 265.5347928059.

The spelling of 18722520 in words is "eighteen million, seven hundred twenty-two thousand, five hundred twenty".