639769424717 has 2 divisors, whose sum is σ = 639769424718. Its totient is φ = 639769424716.

The previous prime is 639769424711. The next prime is 639769424729. The reversal of 639769424717 is 717424967936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 486047403241 + 153722021476 = 697171^2 + 392074^2 .

It is a cyclic number.

It is not a de Polignac number, because 639769424717 - 2³⁰ = 638695682893 is a prime.

It is a super-3 number, since 3×639769424717³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639769424711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319884712358 + 319884712359.

It is an arithmetic number, because the mean of its divisors is an integer number (319884712359).

Almost surely, 2^639769424717 is an apocalyptic number.

It is an amenable number.

639769424717 is a deficient number, since it is larger than the sum of its proper divisors (1).

639769424717 is an equidigital number, since it uses as much as digits as its factorization.

639769424717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96018048, while the sum is 65.

The spelling of 639769424717 in words is "six hundred thirty-nine billion, seven hundred sixty-nine million, four hundred twenty-four thousand, seven hundred seventeen".