21915011872 has 48 divisors (see below), whose sum is σ = 46742415552. Its totient is φ = 10054022400.

The previous prime is 21915011779. The next prime is 21915011887. The reversal of 21915011872 is 27811051912.

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, 88254 + ... + 227197.

It is an arithmetic number, because the mean of its divisors is an integer number (973800324).

Almost surely, 2^21915011872 is an apocalyptic number.

It is an amenable number.

21915011872 is an abundant number, since it is smaller than the sum of its proper divisors (24827403680).

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

21915011872 is a wasteful number, since it uses less digits than its factorization.

21915011872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315641 (or 315633 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 37.

The spelling of 21915011872 in words is "twenty-one billion, nine hundred fifteen million, eleven thousand, eight hundred seventy-two".