643641171 has 8 divisors (see below), whose sum is σ = 876447744. Its totient is φ = 419964360.

The previous prime is 643641161. The next prime is 643641211. The reversal of 643641171 is 171146346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 643641171 - 2⁵ = 643641139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643641161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2282275 + ... + 2282556.

It is an arithmetic number, because the mean of its divisors is an integer number (109555968).

Almost surely, 2^643641171 is an apocalyptic number.

643641171 is a deficient number, since it is larger than the sum of its proper divisors (232806573).

643641171 is a wasteful number, since it uses less digits than its factorization.

643641171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4564881.

The product of its digits is 12096, while the sum is 33.

The square root of 643641171 is about 25370.0841740819. The cubic root of 643641171 is about 863.4050916372.

The spelling of 643641171 in words is "six hundred forty-three million, six hundred forty-one thousand, one hundred seventy-one".