125577509 has 2 divisors, whose sum is σ = 125577510. Its totient is φ = 125577508.

The previous prime is 125577499. The next prime is 125577523. The reversal of 125577509 is 905775521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124389409 + 1188100 = 11153^2 + 1090^2 .

It is a cyclic number.

It is not a de Polignac number, because 125577509 - 2⁸ = 125577253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125577209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62788754 + 62788755.

It is an arithmetic number, because the mean of its divisors is an integer number (62788755).

Almost surely, 2^125577509 is an apocalyptic number.

It is an amenable number.

125577509 is a deficient number, since it is larger than the sum of its proper divisors (1).

125577509 is an equidigital number, since it uses as much as digits as its factorization.

125577509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 110250, while the sum is 41.

The square root of 125577509 is about 11206.1371132072. The cubic root of 125577509 is about 500.7688291974.

The spelling of 125577509 in words is "one hundred twenty-five million, five hundred seventy-seven thousand, five hundred nine".