125968561 has 2 divisors, whose sum is σ = 125968562. Its totient is φ = 125968560.

The previous prime is 125968559. The next prime is 125968597. The reversal of 125968561 is 165869521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112784400 + 13184161 = 10620^2 + 3631^2 .

It is a cyclic number.

It is not a de Polignac number, because 125968561 - 2¹ = 125968559 is a prime.

Together with 125968559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (125968541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62984280 + 62984281.

It is an arithmetic number, because the mean of its divisors is an integer number (62984281).

Almost surely, 2^125968561 is an apocalyptic number.

It is an amenable number.

125968561 is a deficient number, since it is larger than the sum of its proper divisors (1).

125968561 is an equidigital number, since it uses as much as digits as its factorization.

125968561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 43.

The square root of 125968561 is about 11223.5716685911. The cubic root of 125968561 is about 501.2880934476.

The spelling of 125968561 in words is "one hundred twenty-five million, nine hundred sixty-eight thousand, five hundred sixty-one".