643868087271 has 32 divisors (see below), whose sum is σ = 865564753920. Its totient is φ = 425727640800.

The previous prime is 643868087251. The next prime is 643868087323. The reversal of 643868087271 is 172780868346.

It is a happy number.

It is not a de Polignac number, because 643868087271 - 2²⁵ = 643834532839 is a prime.

It is a super-2 number, since 2×643868087271² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643868087201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 180302916 + ... + 180306486.

It is an arithmetic number, because the mean of its divisors is an integer number (27048898560).

Almost surely, 2^643868087271 is an apocalyptic number.

643868087271 is a deficient number, since it is larger than the sum of its proper divisors (221696666649).

643868087271 is a wasteful number, since it uses less digits than its factorization.

643868087271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4787.

The product of its (nonzero) digits is 21676032, while the sum is 60.

The spelling of 643868087271 in words is "six hundred forty-three billion, eight hundred sixty-eight million, eighty-seven thousand, two hundred seventy-one".