21585004417 has 8 divisors (see below), whose sum is σ = 21635960192. Its totient is φ = 21534076800.

The previous prime is 21585004387. The next prime is 21585004423. The reversal of 21585004417 is 71440058512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21585004417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21585004457) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2640817 + ... + 2648977.

It is an arithmetic number, because the mean of its divisors is an integer number (2704495024).

Almost surely, 2^21585004417 is an apocalyptic number.

It is an amenable number.

21585004417 is a deficient number, since it is larger than the sum of its proper divisors (50955775).

21585004417 is an equidigital number, since it uses as much as digits as its factorization.

21585004417 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14079.

The product of its (nonzero) digits is 44800, while the sum is 37.

The spelling of 21585004417 in words is "twenty-one billion, five hundred eighty-five million, four thousand, four hundred seventeen".