638674788029 has 2 divisors, whose sum is σ = 638674788030. Its totient is φ = 638674788028.

The previous prime is 638674788023. The next prime is 638674788119. The reversal of 638674788029 is 920887476836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 636979572100 + 1695215929 = 798110^2 + 41173^2 .

It is a cyclic number.

It is not a de Polignac number, because 638674788029 - 2²⁰ = 638673739453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 638674788029.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638674788023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319337394014 + 319337394015.

It is an arithmetic number, because the mean of its divisors is an integer number (319337394015).

Almost surely, 2^638674788029 is an apocalyptic number.

It is an amenable number.

638674788029 is a deficient number, since it is larger than the sum of its proper divisors (1).

638674788029 is an equidigital number, since it uses as much as digits as its factorization.

638674788029 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 195084288, while the sum is 68.

The spelling of 638674788029 in words is "six hundred thirty-eight billion, six hundred seventy-four million, seven hundred eighty-eight thousand, twenty-nine".