21376638771899 has 2 divisors, whose sum is σ = 21376638771900. Its totient is φ = 21376638771898.

The previous prime is 21376638771779. The next prime is 21376638771941. The reversal of 21376638771899 is 99817783667312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21376638771899 - 2⁸ = 21376638771643 is a prime.

It is not a weakly prime, because it can be changed into another prime (21376638771199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10688319385949 + 10688319385950.

It is an arithmetic number, because the mean of its divisors is an integer number (10688319385950).

Almost surely, 2^{21376638771899} is an apocalyptic number.

21376638771899 is a deficient number, since it is larger than the sum of its proper divisors (1).

21376638771899 is an equidigital number, since it uses as much as digits as its factorization.

21376638771899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152216576, while the sum is 77.

The spelling of 21376638771899 in words is "twenty-one trillion, three hundred seventy-six billion, six hundred thirty-eight million, seven hundred seventy-one thousand, eight hundred ninety-nine".