126251513071681 has 2 divisors, whose sum is σ = 126251513071682. Its totient is φ = 126251513071680.

The previous prime is 126251513071643. The next prime is 126251513071709. The reversal of 126251513071681 is 186170315152621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 82385847522225 + 43865665549456 = 9076665^2 + 6623116^2 .

It is a cyclic number.

It is not a de Polignac number, because 126251513071681 - 2⁷ = 126251513071553 is a prime.

It is a super-2 number, since 2×126251513071681² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (126251513071601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63125756535840 + 63125756535841.

It is an arithmetic number, because the mean of its divisors is an integer number (63125756535841).

Almost surely, 2^{126251513071681} is an apocalyptic number.

It is an amenable number.

126251513071681 is a deficient number, since it is larger than the sum of its proper divisors (1).

126251513071681 is an equidigital number, since it uses as much as digits as its factorization.

126251513071681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 604800, while the sum is 49.

The spelling of 126251513071681 in words is "one hundred twenty-six trillion, two hundred fifty-one billion, five hundred thirteen million, seventy-one thousand, six hundred eighty-one".