639370368 has 512 divisors, whose sum is σ = 2467584000. Its totient is φ = 158257152.

The previous prime is 639370363. The next prime is 639370409. The reversal of 639370368 is 863073936.

It is a happy number.

639370368 is a `hidden beast` number, since 639 + 3 + 7 + 0 + 3 + 6 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (639370363) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5975371 + ... + 5975477.

It is an arithmetic number, because the mean of its divisors is an integer number (4819500).

Almost surely, 2^639370368 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 639370368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1233792000).

639370368 is an abundant number, since it is smaller than the sum of its proper divisors (1828213632).

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

639370368 is a wasteful number, since it uses less digits than its factorization.

639370368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 45.

The square root of 639370368 is about 25285.7740241425. The cubic root of 639370368 is about 861.4911789069.

The spelling of 639370368 in words is "six hundred thirty-nine million, three hundred seventy thousand, three hundred sixty-eight".