21726465191 has 2 divisors, whose sum is σ = 21726465192. Its totient is φ = 21726465190.

The previous prime is 21726465181. The next prime is 21726465259. The reversal of 21726465191 is 19156462712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21726465191 - 2³⁰ = 20652723367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21726465181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10863232595 + 10863232596.

It is an arithmetic number, because the mean of its divisors is an integer number (10863232596).

Almost surely, 2^21726465191 is an apocalyptic number.

21726465191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21726465191 is an equidigital number, since it uses as much as digits as its factorization.

21726465191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 44.

The spelling of 21726465191 in words is "twenty-one billion, seven hundred twenty-six million, four hundred sixty-five thousand, one hundred ninety-one".