639196704 has 96 divisors (see below), whose sum is σ = 1881109440. Its totient is φ = 211147776.

The previous prime is 639196699. The next prime is 639196709. The reversal of 639196704 is 407691936.

639196704 is a `hidden beast` number, since 639 + 1 + 9 + 6 + 7 + 0 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (639196699) and next prime (639196709).

It is a tau number, because it is divible by the number of its divisors (96).

It is a self number, because there is not a number n which added to its sum of digits gives 639196704.

It is not an unprimeable number, because it can be changed into a prime (639196709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94359 + ... + 100905.

It is an arithmetic number, because the mean of its divisors is an integer number (19594890).

Almost surely, 2^639196704 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 639196704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940554720).

639196704 is an abundant number, since it is smaller than the sum of its proper divisors (1241912736).

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

639196704 is a wasteful number, since it uses less digits than its factorization.

639196704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6679 (or 6665 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 639196704 is about 25282.3397651404. The cubic root of 639196704 is about 861.4131732318.

The spelling of 639196704 in words is "six hundred thirty-nine million, one hundred ninety-six thousand, seven hundred four".