21871896677 has 2 divisors, whose sum is σ = 21871896678. Its totient is φ = 21871896676.

The previous prime is 21871896623. The next prime is 21871896689. The reversal of 21871896677 is 77669817812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20502230596 + 1369666081 = 143186^2 + 37009^2 .

It is a cyclic number.

It is not a de Polignac number, because 21871896677 - 2⁸ = 21871896421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21871896877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10935948338 + 10935948339.

It is an arithmetic number, because the mean of its divisors is an integer number (10935948339).

Almost surely, 2^21871896677 is an apocalyptic number.

It is an amenable number.

21871896677 is a deficient number, since it is larger than the sum of its proper divisors (1).

21871896677 is an equidigital number, since it uses as much as digits as its factorization.

21871896677 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14224896, while the sum is 62.

The spelling of 21871896677 in words is "twenty-one billion, eight hundred seventy-one million, eight hundred ninety-six thousand, six hundred seventy-seven".