639425598 has 96 divisors (see below), whose sum is σ = 1528657920. Its totient is φ = 177730560.

The previous prime is 639425597. The next prime is 639425617. The reversal of 639425598 is 895524936.

It is a self number, because there is not a number n which added to its sum of digits gives 639425598.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639425593) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3312990 + ... + 3313182.

It is an arithmetic number, because the mean of its divisors is an integer number (15923520).

Almost surely, 2^639425598 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639425598, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (764328960).

639425598 is an abundant number, since it is smaller than the sum of its proper divisors (889232322).

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

639425598 is a wasteful number, since it uses less digits than its factorization.

639425598 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462 (or 455 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 51.

The square root of 639425598 is about 25286.8661166227. The cubic root of 639425598 is about 861.5159839288.

The spelling of 639425598 in words is "six hundred thirty-nine million, four hundred twenty-five thousand, five hundred ninety-eight".