639231 has 8 divisors (see below), whose sum is σ = 873264. Its totient is φ = 415680.

The previous prime is 639211. The next prime is 639253. The reversal of 639231 is 132936.

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

It is not a de Polignac number, because 639231 - 2⁶ = 639167 is a prime.

It is a super-2 number, since 2×639231² = 817232542722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639211) 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, 2476 + ... + 2721.

It is an arithmetic number, because the mean of its divisors is an integer number (109158).

2⁶³⁹²³¹ is an apocalyptic number.

639231 is a deficient number, since it is larger than the sum of its proper divisors (234033).

639231 is a wasteful number, since it uses less digits than its factorization.

639231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5241.

The product of its digits is 972, while the sum is 24.

The square root of 639231 is about 799.5192305380. The cubic root of 639231 is about 86.1428579286.

The spelling of 639231 in words is "six hundred thirty-nine thousand, two hundred thirty-one".