638676505007 has 4 divisors (see below), whose sum is σ = 638682337656. Its totient is φ = 638670672360.

The previous prime is 638676505003. The next prime is 638676505013. The reversal of 638676505007 is 700505676836.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 638676505007 - 2² = 638676505003 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 638676505007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638676505003) 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, 2748869 + ... + 2972142.

It is an arithmetic number, because the mean of its divisors is an integer number (159670584414).

Almost surely, 2^638676505007 is an apocalyptic number.

638676505007 is a deficient number, since it is larger than the sum of its proper divisors (5832649).

638676505007 is a wasteful number, since it uses less digits than its factorization.

638676505007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5832648.

The product of its (nonzero) digits is 6350400, while the sum is 53.

The spelling of 638676505007 in words is "six hundred thirty-eight billion, six hundred seventy-six million, five hundred five thousand, seven".