639012 has 48 divisors (see below), whose sum is σ = 1677312. Its totient is φ = 187680.

The previous prime is 639011. The next prime is 639043. The reversal of 639012 is 210936.

It is a super-2 number, since 2×639012² = 816672672288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 639012.

It is not an unprimeable number, because it can be changed into a prime (639011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6153 + ... + 6255.

It is an arithmetic number, because the mean of its divisors is an integer number (34944).

2⁶³⁹⁰¹² 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 639012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (838656).

639012 is an abundant number, since it is smaller than the sum of its proper divisors (1038300).

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

639012 is a wasteful number, since it uses less digits than its factorization.

639012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 639012 is about 799.3822614995. The cubic root of 639012 is about 86.1330193149.

Adding to 639012 its reverse (210936), we get a palindrome (849948).

It can be divided in two parts, 63901 and 2, that added together give a triangular number (63903 = T₃₅₇).

The spelling of 639012 in words is "six hundred thirty-nine thousand, twelve".