21757522308 has 12 divisors (see below), whose sum is σ = 50767552080. Its totient is φ = 7252507432.

The previous prime is 21757522279. The next prime is 21757522321. The reversal of 21757522308 is 80322575712.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 21757522308.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 906563418 + ... + 906563441.

It is an arithmetic number, because the mean of its divisors is an integer number (4230629340).

Almost surely, 2^21757522308 is an apocalyptic number.

It is an amenable number.

21757522308 is an abundant number, since it is smaller than the sum of its proper divisors (29010029772).

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

21757522308 is a wasteful number, since it uses less digits than its factorization.

21757522308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1813126866 (or 1813126864 counting only the distinct ones).

The product of its (nonzero) digits is 235200, while the sum is 42.

The spelling of 21757522308 in words is "twenty-one billion, seven hundred fifty-seven million, five hundred twenty-two thousand, three hundred eight".