639979642151 has 4 divisors (see below), whose sum is σ = 677625503472. Its totient is φ = 602333780832.

The previous prime is 639979642103. The next prime is 639979642163. The reversal of 639979642151 is 151246979936.

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 639979642151 - 2²² = 639975447847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639979642171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18822930635 + ... + 18822930668.

It is an arithmetic number, because the mean of its divisors is an integer number (169406375868).

Almost surely, 2^639979642151 is an apocalyptic number.

639979642151 is a deficient number, since it is larger than the sum of its proper divisors (37645861321).

639979642151 is a wasteful number, since it uses less digits than its factorization.

639979642151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37645861320.

The product of its digits is 22044960, while the sum is 62.

The spelling of 639979642151 in words is "six hundred thirty-nine billion, nine hundred seventy-nine million, six hundred forty-two thousand, one hundred fifty-one".