639197328 has 160 divisors (see below), whose sum is σ = 2073295872. Its totient is φ = 164851200.

The previous prime is 639197303. The next prime is 639197329. The reversal of 639197328 is 823791936.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (639197329) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 601918 + ... + 602978.

Almost surely, 2^639197328 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639197328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1036647936).

639197328 is an abundant number, since it is smaller than the sum of its proper divisors (1434098544).

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

639197328 is a wasteful number, since it uses less digits than its factorization.

639197328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253 (or 1247 counting only the distinct ones).

The product of its digits is 489888, while the sum is 48.

The square root of 639197328 is about 25282.3521057674. The cubic root of 639197328 is about 861.4134535428.

The spelling of 639197328 in words is "six hundred thirty-nine million, one hundred ninety-seven thousand, three hundred twenty-eight".