21550651570 has 32 divisors (see below), whose sum is σ = 45059544576. Its totient is φ = 7267665600.

The previous prime is 21550651541. The next prime is 21550651589. The reversal of 21550651570 is 7515605512.

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, 2519226 + ... + 2527765.

It is an arithmetic number, because the mean of its divisors is an integer number (1408110768).

Almost surely, 2^21550651570 is an apocalyptic number.

21550651570 is an abundant number, since it is smaller than the sum of its proper divisors (23508893006).

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

21550651570 is a wasteful number, since it uses less digits than its factorization.

21550651570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5047066.

The product of its (nonzero) digits is 52500, while the sum is 37.

The spelling of 21550651570 in words is "twenty-one billion, five hundred fifty million, six hundred fifty-one thousand, five hundred seventy".