21164542377983 has 4 divisors (see below), whose sum is σ = 21370023372048. Its totient is φ = 20959061383920.

The previous prime is 21164542377971. The next prime is 21164542377989. The reversal of 21164542377983 is 38977324546112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21164542377983 - 2²⁸ = 21164273942527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21164542377989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102740496878 + ... + 102740497083.

It is an arithmetic number, because the mean of its divisors is an integer number (5342505843012).

Almost surely, 2^{21164542377983} is an apocalyptic number.

21164542377983 is a deficient number, since it is larger than the sum of its proper divisors (205480994065).

21164542377983 is a wasteful number, since it uses less digits than its factorization.

21164542377983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205480994064.

The product of its digits is 60963840, while the sum is 62.

The spelling of 21164542377983 in words is "twenty-one trillion, one hundred sixty-four billion, five hundred forty-two million, three hundred seventy-seven thousand, nine hundred eighty-three".