21610548165 has 16 divisors (see below), whose sum is σ = 35092951488. Its totient is φ = 11353600896.

The previous prime is 21610548161. The next prime is 21610548191. The reversal of 21610548165 is 56184501612.

It is not a de Polignac number, because 21610548165 - 2² = 21610548161 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21610548161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10750512 + ... + 10752521.

It is an arithmetic number, because the mean of its divisors is an integer number (2193309468).

Almost surely, 2^21610548165 is an apocalyptic number.

It is an amenable number.

21610548165 is a deficient number, since it is larger than the sum of its proper divisors (13482403323).

21610548165 is a wasteful number, since it uses less digits than its factorization.

21610548165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21503108.

The product of its (nonzero) digits is 57600, while the sum is 39.

The spelling of 21610548165 in words is "twenty-one billion, six hundred ten million, five hundred forty-eight thousand, one hundred sixty-five".