638107832171 has 2 divisors, whose sum is σ = 638107832172. Its totient is φ = 638107832170.

The previous prime is 638107832119. The next prime is 638107832177. The reversal of 638107832171 is 171238701836.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638107832171 is a prime.

It is not a weakly prime, because it can be changed into another prime (638107832177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319053916085 + 319053916086.

It is an arithmetic number, because the mean of its divisors is an integer number (319053916086).

Almost surely, 2^638107832171 is an apocalyptic number.

638107832171 is a deficient number, since it is larger than the sum of its proper divisors (1).

638107832171 is an equidigital number, since it uses as much as digits as its factorization.

638107832171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 338688, while the sum is 47.

The spelling of 638107832171 in words is "six hundred thirty-eight billion, one hundred seven million, eight hundred thirty-two thousand, one hundred seventy-one".