21977464319 has 4 divisors (see below), whose sum is σ = 22003050120. Its totient is φ = 21951878520.

The previous prime is 21977464297. The next prime is 21977464337. The reversal of 21977464319 is 91346477912.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21977464319 is a prime.

It is a super-2 number, since 2×21977464319² (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 (21977464339) 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, 12791612 + ... + 12793329.

It is an arithmetic number, because the mean of its divisors is an integer number (5500762530).

Almost surely, 2^21977464319 is an apocalyptic number.

21977464319 is a deficient number, since it is larger than the sum of its proper divisors (25585801).

21977464319 is an equidigital number, since it uses as much as digits as its factorization.

21977464319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25585800.

The product of its digits is 2286144, while the sum is 53.

The spelling of 21977464319 in words is "twenty-one billion, nine hundred seventy-seven million, four hundred sixty-four thousand, three hundred nineteen".