639395752 has 16 divisors (see below), whose sum is σ = 1261965600. Its totient is φ = 302871600.

The previous prime is 639395747. The next prime is 639395753. The reversal of 639395752 is 257593936.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 639395696 and 639395705.

It is not an unprimeable number, because it can be changed into a prime (639395753) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2103124 + ... + 2103427.

It is an arithmetic number, because the mean of its divisors is an integer number (78872850).

Almost surely, 2^639395752 is an apocalyptic number.

It is an amenable number.

639395752 is a deficient number, since it is larger than the sum of its proper divisors (622569848).

639395752 is a wasteful number, since it uses less digits than its factorization.

639395752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4206576 (or 4206572 counting only the distinct ones).

The product of its digits is 1530900, while the sum is 49.

The square root of 639395752 is about 25286.2759614776. The cubic root of 639395752 is about 861.5025796035.

The spelling of 639395752 in words is "six hundred thirty-nine million, three hundred ninety-five thousand, seven hundred fifty-two".