21372656208 has 40 divisors (see below), whose sum is σ = 55911600000. Its totient is φ = 7034037504.

The previous prime is 21372656203. The next prime is 21372656219. The reversal of 21372656208 is 80265627312.

It is a self number, because there is not a number n which added to its sum of digits gives 21372656208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21372656203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2814333 + ... + 2821916.

It is an arithmetic number, because the mean of its divisors is an integer number (1397790000).

Almost surely, 2^21372656208 is an apocalyptic number.

It is an amenable number.

21372656208 is an abundant number, since it is smaller than the sum of its proper divisors (34538943792).

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

21372656208 is a wasteful number, since it uses less digits than its factorization.

21372656208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5636339 (or 5636333 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 42.

The spelling of 21372656208 in words is "twenty-one billion, three hundred seventy-two million, six hundred fifty-six thousand, two hundred eight".