125843561 has 2 divisors, whose sum is σ = 125843562. Its totient is φ = 125843560.

The previous prime is 125843483. The next prime is 125843563. The reversal of 125843561 is 165348521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84640000 + 41203561 = 9200^2 + 6419^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-125843561 is a prime.

It is a Sophie Germain prime.

Together with 125843563, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (125843563) 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, 62921780 + 62921781.

It is an arithmetic number, because the mean of its divisors is an integer number (62921781).

Almost surely, 2^125843561 is an apocalyptic number.

It is an amenable number.

125843561 is a deficient number, since it is larger than the sum of its proper divisors (1).

125843561 is an equidigital number, since it uses as much as digits as its factorization.

125843561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28800, while the sum is 35.

The square root of 125843561 is about 11218.0016491352. The cubic root of 125843561 is about 501.1222273272.

The spelling of 125843561 in words is "one hundred twenty-five million, eight hundred forty-three thousand, five hundred sixty-one".