21585795945 has 32 divisors (see below), whose sum is σ = 40027115520. Its totient is φ = 9728806080.

The previous prime is 21585795929. The next prime is 21585795949. The reversal of 21585795945 is 54959758512.

It is not a de Polignac number, because 21585795945 - 2⁴ = 21585795929 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21585795949) by changing a digit.

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, 1440285 + ... + 1455194.

It is an arithmetic number, because the mean of its divisors is an integer number (1250847360).

Almost surely, 2^21585795945 is an apocalyptic number.

It is an amenable number.

21585795945 is a deficient number, since it is larger than the sum of its proper divisors (18441319575).

21585795945 is a wasteful number, since it uses less digits than its factorization.

21585795945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2895565.

The product of its digits is 22680000, while the sum is 60.

The spelling of 21585795945 in words is "twenty-one billion, five hundred eighty-five million, seven hundred ninety-five thousand, nine hundred forty-five".