21469593920 has 42 divisors (see below), whose sum is σ = 51130712826. Its totient is φ = 8586789120.

The previous prime is 21469593917. The next prime is 21469593949. The reversal of 21469593920 is 2939596412.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 17175675136 + 4293918784 = 131056^2 + 65528^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2617025 + ... + 2625215.

Almost surely, 2^21469593920 is an apocalyptic number.

21469593920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21469593920 is an abundant number, since it is smaller than the sum of its proper divisors (29661118906).

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

21469593920 is an frugal number, since it uses more digits than its factorization.

21469593920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16399 (or 8198 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 50.

The spelling of 21469593920 in words is "twenty-one billion, four hundred sixty-nine million, five hundred ninety-three thousand, nine hundred twenty".