125981857 has 2 divisors, whose sum is σ = 125981858. Its totient is φ = 125981856.

The previous prime is 125981851. The next prime is 125981893. The reversal of 125981857 is 758189521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 111851776 + 14130081 = 10576^2 + 3759^2 .

It is an emirp because it is prime and its reverse (758189521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 125981857 - 2⁷ = 125981729 is a prime.

It is not a weakly prime, because it can be changed into another prime (125981851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62990928 + 62990929.

It is an arithmetic number, because the mean of its divisors is an integer number (62990929).

Almost surely, 2^125981857 is an apocalyptic number.

It is an amenable number.

125981857 is a deficient number, since it is larger than the sum of its proper divisors (1).

125981857 is an equidigital number, since it uses as much as digits as its factorization.

125981857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 201600, while the sum is 46.

The square root of 125981857 is about 11224.1639777758. The cubic root of 125981857 is about 501.3057298376.

The spelling of 125981857 in words is "one hundred twenty-five million, nine hundred eighty-one thousand, eight hundred fifty-seven".