125817553 has 2 divisors, whose sum is σ = 125817554. Its totient is φ = 125817552.

The previous prime is 125817529. The next prime is 125817569. The reversal of 125817553 is 355718521.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123921424 + 1896129 = 11132^2 + 1377^2 .

It is a cyclic number.

It is not a de Polignac number, because 125817553 - 2¹⁷ = 125686481 is a prime.

It is not a weakly prime, because it can be changed into another prime (125814553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62908776 + 62908777.

It is an arithmetic number, because the mean of its divisors is an integer number (62908777).

Almost surely, 2^125817553 is an apocalyptic number.

It is an amenable number.

125817553 is a deficient number, since it is larger than the sum of its proper divisors (1).

125817553 is an equidigital number, since it uses as much as digits as its factorization.

125817553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42000, while the sum is 37.

The square root of 125817553 is about 11216.8423809912. The cubic root of 125817553 is about 501.0877027563.

The spelling of 125817553 in words is "one hundred twenty-five million, eight hundred seventeen thousand, five hundred fifty-three".