21168531589539 has 8 divisors (see below), whose sum is σ = 28250297828352. Its totient is φ = 14099559871880.

The previous prime is 21168531589487. The next prime is 21168531589561. The reversal of 21168531589539 is 93598513586112.

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 21168531589539 - 2²⁴ = 21168514812323 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21168531589539.

It is not an unprimeable number, because it can be changed into a prime (21168531588539) 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, 3198626427 + ... + 3198633044.

It is an arithmetic number, because the mean of its divisors is an integer number (3531287228544).

Almost surely, 2^{21168531589539} is an apocalyptic number.

21168531589539 is a deficient number, since it is larger than the sum of its proper divisors (7081766238813).

21168531589539 is a wasteful number, since it uses less digits than its factorization.

21168531589539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6397260577.

The product of its digits is 69984000, while the sum is 66.

The spelling of 21168531589539 in words is "twenty-one trillion, one hundred sixty-eight billion, five hundred thirty-one million, five hundred eighty-nine thousand, five hundred thirty-nine".