21642296171 has 2 divisors, whose sum is σ = 21642296172. Its totient is φ = 21642296170.

The previous prime is 21642296153. The next prime is 21642296173. The reversal of 21642296171 is 17169224612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21642296171 - 2⁶ = 21642296107 is a prime.

It is a super-2 number, since 2×21642296171² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 21642296173, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21642296173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10821148085 + 10821148086.

It is an arithmetic number, because the mean of its divisors is an integer number (10821148086).

Almost surely, 2^21642296171 is an apocalyptic number.

21642296171 is a deficient number, since it is larger than the sum of its proper divisors (1).

21642296171 is an equidigital number, since it uses as much as digits as its factorization.

21642296171 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 41.

The spelling of 21642296171 in words is "twenty-one billion, six hundred forty-two million, two hundred ninety-six thousand, one hundred seventy-one".