63813899557 has 2 divisors, whose sum is σ = 63813899558. Its totient is φ = 63813899556.

The previous prime is 63813899509. The next prime is 63813899581. The reversal of 63813899557 is 75599831836.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36465339681 + 27348559876 = 190959^2 + 165374^2 .

It is a cyclic number.

It is not a de Polignac number, because 63813899557 - 2²³ = 63805510949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63813899587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31906949778 + 31906949779.

It is an arithmetic number, because the mean of its divisors is an integer number (31906949779).

Almost surely, 2^63813899557 is an apocalyptic number.

It is an amenable number.

63813899557 is a deficient number, since it is larger than the sum of its proper divisors (1).

63813899557 is an equidigital number, since it uses as much as digits as its factorization.

63813899557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48988800, while the sum is 64.

The spelling of 63813899557 in words is "sixty-three billion, eight hundred thirteen million, eight hundred ninety-nine thousand, five hundred fifty-seven".