21570849924 has 48 divisors (see below), whose sum is σ = 54630524928. Its totient is φ = 6584917248.

The previous prime is 21570849913. The next prime is 21570849991. The reversal of 21570849924 is 42994807512.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 524577 + ... + 564200.

It is an arithmetic number, because the mean of its divisors is an integer number (1138135936).

Almost surely, 2^21570849924 is an apocalyptic number.

It is an amenable number.

21570849924 is an abundant number, since it is smaller than the sum of its proper divisors (33059675004).

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

21570849924 is a wasteful number, since it uses less digits than its factorization.

21570849924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1088924 (or 1088922 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 51.

The spelling of 21570849924 in words is "twenty-one billion, five hundred seventy million, eight hundred forty-nine thousand, nine hundred twenty-four".