21617022945 has 32 divisors (see below), whose sum is σ = 41853466368. Its totient is φ = 9300768768.

The previous prime is 21617022919. The next prime is 21617022953. The reversal of 21617022945 is 54922071612.

It is not a de Polignac number, because 21617022945 - 2¹¹ = 21617020897 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6053404 + ... + 6056973.

It is an arithmetic number, because the mean of its divisors is an integer number (1307920824).

Almost surely, 2^21617022945 is an apocalyptic number.

It is an amenable number.

21617022945 is a deficient number, since it is larger than the sum of its proper divisors (20236443423).

21617022945 is a wasteful number, since it uses less digits than its factorization.

21617022945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12110409.

The product of its (nonzero) digits is 60480, while the sum is 39.

The spelling of 21617022945 in words is "twenty-one billion, six hundred seventeen million, twenty-two thousand, nine hundred forty-five".