21877948639 has 8 divisors (see below), whose sum is σ = 23132695040. Its totient is φ = 20633529816.

The previous prime is 21877948597. The next prime is 21877948709. The reversal of 21877948639 is 93684977812.

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 21877948639 - 2⁷ = 21877948511 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 (21877948139) 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, 2577537 + ... + 2586010.

It is an arithmetic number, because the mean of its divisors is an integer number (2891586880).

Almost surely, 2^21877948639 is an apocalyptic number.

21877948639 is a deficient number, since it is larger than the sum of its proper divisors (1254746401).

21877948639 is a wasteful number, since it uses less digits than its factorization.

21877948639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5163789.

The product of its digits is 36578304, while the sum is 64.

The spelling of 21877948639 in words is "twenty-one billion, eight hundred seventy-seven million, nine hundred forty-eight thousand, six hundred thirty-nine".