21376638771841 has 16 divisors (see below), whose sum is σ = 21471853810176. Its totient is φ = 21281641030656.

The previous prime is 21376638771779. The next prime is 21376638771899. The reversal of 21376638771841 is 14817783667312.

It is a cyclic number.

It is not a de Polignac number, because 21376638771841 - 2²³ = 21376630383233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21376638771941) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2048939361 + ... + 2048949793.

It is an arithmetic number, because the mean of its divisors is an integer number (1341990863136).

Almost surely, 2^{21376638771841} is an apocalyptic number.

It is an amenable number.

21376638771841 is a deficient number, since it is larger than the sum of its proper divisors (95215038335).

21376638771841 is a wasteful number, since it uses less digits than its factorization.

21376638771841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19992.

The product of its digits is 56899584, while the sum is 64.

The spelling of 21376638771841 in words is "twenty-one trillion, three hundred seventy-six billion, six hundred thirty-eight million, seven hundred seventy-one thousand, eight hundred forty-one".