639423654 has 16 divisors (see below), whose sum is σ = 1290800448. Its totient is φ = 211149032.

The previous prime is 639423643. The next prime is 639423661. The reversal of 639423654 is 456324936.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 497352 + ... + 498635.

It is an arithmetic number, because the mean of its divisors is an integer number (80675028).

Almost surely, 2^639423654 is an apocalyptic number.

639423654 is an abundant number, since it is smaller than the sum of its proper divisors (651376794).

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

639423654 is a wasteful number, since it uses less digits than its factorization.

639423654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996099.

The product of its digits is 466560, while the sum is 42.

The square root of 639423654 is about 25286.8276776665. The cubic root of 639423654 is about 861.5151108594.

The spelling of 639423654 in words is "six hundred thirty-nine million, four hundred twenty-three thousand, six hundred fifty-four".