639312 has 40 divisors (see below), whose sum is σ = 1740960. Its totient is φ = 201600.

The previous prime is 639311. The next prime is 639329. The reversal of 639312 is 213936.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 562 + ... + 1262.

It is an arithmetic number, because the mean of its divisors is an integer number (43524).

2⁶³⁹³¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (870480).

639312 is an abundant number, since it is smaller than the sum of its proper divisors (1101648).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639312 is a wasteful number, since it uses less digits than its factorization.

639312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 731 (or 725 counting only the distinct ones).

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

The square root of 639312 is about 799.5698843753. The cubic root of 639312 is about 86.1464962987.

The spelling of 639312 in words is "six hundred thirty-nine thousand, three hundred twelve".