21643270164171 has 8 divisors (see below), whose sum is σ = 32064103946960. Its totient is φ = 14428846776096.

The previous prime is 21643270164161. The next prime is 21643270164203. The reversal of 21643270164171 is 17146107234612.

21643270164171 is a `hidden beast` number, since 2 + 16 + 43 + 270 + 164 + 171 = 666.

It is not a de Polignac number, because 21643270164171 - 2¹⁰ = 21643270163147 is a prime.

It is a super-2 number, since 2×21643270164171² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21643270164121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400801299310 + ... + 400801299363.

It is an arithmetic number, because the mean of its divisors is an integer number (4008012993370).

Almost surely, 2^{21643270164171} is an apocalyptic number.

21643270164171 is a deficient number, since it is larger than the sum of its proper divisors (10420833782789).

21643270164171 is an equidigital number, since it uses as much as digits as its factorization.

21643270164171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801602598682 (or 801602598676 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

Adding to 21643270164171 its reverse (17146107234612), we get a palindrome (38789377398783).

The spelling of 21643270164171 in words is "twenty-one trillion, six hundred forty-three billion, two hundred seventy million, one hundred sixty-four thousand, one hundred seventy-one".