639746322022217 has 2 divisors, whose sum is σ = 639746322022218. Its totient is φ = 639746322022216.

The previous prime is 639746322022109. The next prime is 639746322022271. The reversal of 639746322022217 is 712220223647936.

Together with next prime (639746322022271) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 405519550650256 + 234226771371961 = 20137516^2 + 15304469^2 .

It is a cyclic number.

It is not a de Polignac number, because 639746322022217 - 2³⁴ = 639729142153033 is a prime.

It is not a weakly prime, because it can be changed into another prime (639746342022217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319873161011108 + 319873161011109.

It is an arithmetic number, because the mean of its divisors is an integer number (319873161011109).

Almost surely, 2^{639746322022217} is an apocalyptic number.

It is an amenable number.

639746322022217 is a deficient number, since it is larger than the sum of its proper divisors (1).

639746322022217 is an equidigital number, since it uses as much as digits as its factorization.

639746322022217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18289152, while the sum is 56.

The spelling of 639746322022217 in words is "six hundred thirty-nine trillion, seven hundred forty-six billion, three hundred twenty-two million, twenty-two thousand, two hundred seventeen".