639099968371 has 2 divisors, whose sum is σ = 639099968372. Its totient is φ = 639099968370.

The previous prime is 639099968363. The next prime is 639099968503. The reversal of 639099968371 is 173869990936.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 639099968371 - 2³ = 639099968363 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 639099968371.

It is not a weakly prime, because it can be changed into another prime (639099968971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319549984185 + 319549984186.

It is an arithmetic number, because the mean of its divisors is an integer number (319549984186).

Almost surely, 2^639099968371 is an apocalyptic number.

639099968371 is a deficient number, since it is larger than the sum of its proper divisors (1).

639099968371 is an equidigital number, since it uses as much as digits as its factorization.

639099968371 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 119042784, while the sum is 70.

The spelling of 639099968371 in words is "six hundred thirty-nine billion, ninety-nine million, nine hundred sixty-eight thousand, three hundred seventy-one".