21131692872671 has 2 divisors, whose sum is σ = 21131692872672. Its totient is φ = 21131692872670.

The previous prime is 21131692872601. The next prime is 21131692872767. The reversal of 21131692872671 is 17627829613112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21131692872671 - 2⁴² = 16733646361567 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21131692872601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565846436335 + 10565846436336.

It is an arithmetic number, because the mean of its divisors is an integer number (10565846436336).

Almost surely, 2^{21131692872671} is an apocalyptic number.

21131692872671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131692872671 is an equidigital number, since it uses as much as digits as its factorization.

21131692872671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3048192, while the sum is 56.

The spelling of 21131692872671 in words is "twenty-one trillion, one hundred thirty-one billion, six hundred ninety-two million, eight hundred seventy-two thousand, six hundred seventy-one".