639422 has 8 divisors (see below), whose sum is σ = 1096176. Its totient is φ = 274032.

The previous prime is 639391. The next prime is 639433. The reversal of 639422 is 224936.

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

It is a junction number, because it is equal to n+sod(n) for n = 639391 and 639400.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22823 + ... + 22850.

It is an arithmetic number, because the mean of its divisors is an integer number (137022).

2⁶³⁹⁴²² is an apocalyptic number.

639422 is a deficient number, since it is larger than the sum of its proper divisors (456754).

639422 is a wasteful number, since it uses less digits than its factorization.

639422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45682.

The product of its digits is 2592, while the sum is 26.

The square root of 639422 is about 799.6386683997. The cubic root of 639422 is about 86.1514368030.

The spelling of 639422 in words is "six hundred thirty-nine thousand, four hundred twenty-two".