639443 has 8 divisors (see below), whose sum is σ = 736512. Its totient is φ = 543816.

The previous prime is 639439. The next prime is 639451. The reversal of 639443 is 344936.

It is a happy number.

639443 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 639443 - 2² = 639439 is a prime.

It is not an unprimeable number, because it can be changed into a prime (639433) 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, 896 + ... + 1442.

It is an arithmetic number, because the mean of its divisors is an integer number (92064).

2⁶³⁹⁴⁴³ is an apocalyptic number.

639443 is a deficient number, since it is larger than the sum of its proper divisors (97069).

639443 is a wasteful number, since it uses less digits than its factorization.

639443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721.

The product of its digits is 7776, while the sum is 29.

The square root of 639443 is about 799.6517992226. The cubic root of 639443 is about 86.1523799258.

The spelling of 639443 in words is "six hundred thirty-nine thousand, four hundred forty-three".