18722446520 has 16 divisors (see below), whose sum is σ = 42125504760. Its totient is φ = 7488978592.

The previous prime is 18722446513. The next prime is 18722446529. The reversal of 18722446520 is 2564422781.

It is a happy number.

It is a super-2 number, since 2×18722446520² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18722446529) 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, 234030542 + ... + 234030621.

Almost surely, 2^18722446520 is an apocalyptic number.

18722446520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18722446520 is an abundant number, since it is smaller than the sum of its proper divisors (23403058240).

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

18722446520 is a wasteful number, since it uses less digits than its factorization.

18722446520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468061174 (or 468061170 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 41.

The spelling of 18722446520 in words is "eighteen billion, seven hundred twenty-two million, four hundred forty-six thousand, five hundred twenty".