638570782877 has 2 divisors, whose sum is σ = 638570782878. Its totient is φ = 638570782876.

The previous prime is 638570782867. The next prime is 638570782907. The reversal of 638570782877 is 778287075836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 587562108676 + 51008674201 = 766526^2 + 225851^2 .

It is a cyclic number.

It is not a de Polignac number, because 638570782877 - 2¹⁸ = 638570520733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638570782867) 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, 319285391438 + 319285391439.

It is an arithmetic number, because the mean of its divisors is an integer number (319285391439).

Almost surely, 2^638570782877 is an apocalyptic number.

It is an amenable number.

638570782877 is a deficient number, since it is larger than the sum of its proper divisors (1).

638570782877 is an equidigital number, since it uses as much as digits as its factorization.

638570782877 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 221276160, while the sum is 68.

The spelling of 638570782877 in words is "six hundred thirty-eight billion, five hundred seventy million, seven hundred eighty-two thousand, eight hundred seventy-seven".