21650555017 has 24 divisors (see below), whose sum is σ = 27958207104. Its totient is φ = 16385301504.

The previous prime is 21650554999. The next prime is 21650555053. The reversal of 21650555017 is 71055505612.

It is a de Polignac number, because none of the positive numbers 2^k-21650555017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21650555057) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 370648 + ... + 425065.

It is an arithmetic number, because the mean of its divisors is an integer number (1164925296).

Almost surely, 2^21650555017 is an apocalyptic number.

It is an amenable number.

21650555017 is a deficient number, since it is larger than the sum of its proper divisors (6307652087).

21650555017 is a wasteful number, since it uses less digits than its factorization.

21650555017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 795769 (or 795756 counting only the distinct ones).

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

The spelling of 21650555017 in words is "twenty-one billion, six hundred fifty million, five hundred fifty-five thousand, seventeen".