21580229436 has 24 divisors (see below), whose sum is σ = 50606908800. Its totient is φ = 7157261232.

The previous prime is 21580229417. The next prime is 21580229441. The reversal of 21580229436 is 63492208512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4516086 + ... + 4520861.

It is an arithmetic number, because the mean of its divisors is an integer number (2108621200).

Almost surely, 2^21580229436 is an apocalyptic number.

It is an amenable number.

21580229436 is an abundant number, since it is smaller than the sum of its proper divisors (29026679364).

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

21580229436 is a wasteful number, since it uses less digits than its factorization.

21580229436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9037153 (or 9037151 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 42.

The spelling of 21580229436 in words is "twenty-one billion, five hundred eighty million, two hundred twenty-nine thousand, four hundred thirty-six".