638860647 has 8 divisors (see below), whose sum is σ = 872590320. Its totient is φ = 415519040.

The previous prime is 638860643. The next prime is 638860667. The reversal of 638860647 is 746068836.

It is a happy number.

638860647 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 638860647 - 2² = 638860643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 638860596 and 638860605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638860643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2596872 + ... + 2597117.

It is an arithmetic number, because the mean of its divisors is an integer number (109073790).

Almost surely, 2^638860647 is an apocalyptic number.

638860647 is a deficient number, since it is larger than the sum of its proper divisors (233729673).

638860647 is a wasteful number, since it uses less digits than its factorization.

638860647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5194033.

The product of its (nonzero) digits is 1161216, while the sum is 48.

The square root of 638860647 is about 25275.6928094958. The cubic root of 638860647 is about 861.2621844090.

The spelling of 638860647 in words is "six hundred thirty-eight million, eight hundred sixty thousand, six hundred forty-seven".