21589569397 has 8 divisors (see below), whose sum is σ = 23573623680. Its totient is φ = 19609076160.

The previous prime is 21589569269. The next prime is 21589569403. The reversal of 21589569397 is 79396598512.

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

It is a cyclic number.

It is not a de Polignac number, because 21589569397 - 2⁷ = 21589569269 is a prime.

It is a super-2 number, since 2×21589569397² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21589569097) 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, 877572 + ... + 901837.

It is an arithmetic number, because the mean of its divisors is an integer number (2946702960).

Almost surely, 2^21589569397 is an apocalyptic number.

It is an amenable number.

21589569397 is a deficient number, since it is larger than the sum of its proper divisors (1984054283).

21589569397 is a wasteful number, since it uses less digits than its factorization.

21589569397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1780523.

The product of its digits is 36741600, while the sum is 64.

The spelling of 21589569397 in words is "twenty-one billion, five hundred eighty-nine million, five hundred sixty-nine thousand, three hundred ninety-seven".