639217271 has 16 divisors (see below), whose sum is σ = 799538688. Its totient is φ = 496471200.

The previous prime is 639217261. The next prime is 639217349. The reversal of 639217271 is 172712936.

It is a cyclic number.

It is not a de Polignac number, because 639217271 - 2²² = 635022967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639217261) 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 15 ways as a sum of consecutive naturals, for example, 10601 + ... + 37293.

It is an arithmetic number, because the mean of its divisors is an integer number (49971168).

Almost surely, 2^639217271 is an apocalyptic number.

639217271 is a deficient number, since it is larger than the sum of its proper divisors (160321417).

639217271 is a wasteful number, since it uses less digits than its factorization.

639217271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27022.

The product of its digits is 31752, while the sum is 38.

The square root of 639217271 is about 25282.7465082415. The cubic root of 639217271 is about 861.4224121690.

The spelling of 639217271 in words is "six hundred thirty-nine million, two hundred seventeen thousand, two hundred seventy-one".