21289595979 has 32 divisors (see below), whose sum is σ = 28959840000. Its totient is φ = 13909737600.

The previous prime is 21289595963. The next prime is 21289595981. The reversal of 21289595979 is 97959598212.

It is a happy number.

It is not a de Polignac number, because 21289595979 - 2⁴ = 21289595963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21289595879) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21015877 + ... + 21016889.

It is an arithmetic number, because the mean of its divisors is an integer number (904995000).

Almost surely, 2^21289595979 is an apocalyptic number.

21289595979 is a deficient number, since it is larger than the sum of its proper divisors (7670244021).

21289595979 is a wasteful number, since it uses less digits than its factorization.

21289595979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1755.

The product of its digits is 36741600, while the sum is 66.

The spelling of 21289595979 in words is "twenty-one billion, two hundred eighty-nine million, five hundred ninety-five thousand, nine hundred seventy-nine".