639860017 has 4 divisors (see below), whose sum is σ = 673536880. Its totient is φ = 606183156.

The previous prime is 639860009. The next prime is 639860029. The reversal of 639860017 is 710068936.

639860017 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 639860017 - 2³ = 639860009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639860917) 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, 16838403 + ... + 16838440.

It is an arithmetic number, because the mean of its divisors is an integer number (168384220).

Almost surely, 2^639860017 is an apocalyptic number.

It is an amenable number.

639860017 is a deficient number, since it is larger than the sum of its proper divisors (33676863).

639860017 is a wasteful number, since it uses less digits than its factorization.

639860017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33676862.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 639860017 is about 25295.4544730867. The cubic root of 639860017 is about 861.7110413832.

The spelling of 639860017 in words is "six hundred thirty-nine million, eight hundred sixty thousand, seventeen".