639395 has 8 divisors (see below), whose sum is σ = 786240. Its totient is φ = 498880.

The previous prime is 639391. The next prime is 639433. The reversal of 639395 is 593936.

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

It is not a de Polignac number, because 639395 - 2² = 639391 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639391) 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, 1355 + ... + 1764.

It is an arithmetic number, because the mean of its divisors is an integer number (98280).

2⁶³⁹³⁹⁵ is an apocalyptic number.

639395 is a deficient number, since it is larger than the sum of its proper divisors (146845).

639395 is a wasteful number, since it uses less digits than its factorization.

639395 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3165.

The product of its digits is 21870, while the sum is 35.

The square root of 639395 is about 799.6217855962. The cubic root of 639395 is about 86.1502241863.

It can be divided in two parts, 639 and 395, that multiplied together give a triangular number (252405 = T₇₁₀).

The spelling of 639395 in words is "six hundred thirty-nine thousand, three hundred ninety-five".