639142 has 16 divisors (see below), whose sum is σ = 1112832. Its totient is φ = 269640.

The previous prime is 639137. The next prime is 639143. The reversal of 639142 is 241936.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639143) 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, 673 + ... + 1315.

It is an arithmetic number, because the mean of its divisors is an integer number (69552).

2⁶³⁹¹⁴² is an apocalyptic number.

639142 is a deficient number, since it is larger than the sum of its proper divisors (473690).

639142 is a wasteful number, since it uses less digits than its factorization.

639142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723.

The product of its digits is 1296, while the sum is 25.

The square root of 639142 is about 799.4635701519. The cubic root of 639142 is about 86.1388598590.

The spelling of 639142 in words is "six hundred thirty-nine thousand, one hundred forty-two".