125575409 has 2 divisors, whose sum is σ = 125575410. Its totient is φ = 125575408.

The previous prime is 125575367. The next prime is 125575501. The reversal of 125575409 is 904575521.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64000000 + 61575409 = 8000^2 + 7847^2 .

It is an emirp because it is prime and its reverse (904575521) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-125575409 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (125575309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62787704 + 62787705.

It is an arithmetic number, because the mean of its divisors is an integer number (62787705).

Almost surely, 2^125575409 is an apocalyptic number.

It is an amenable number.

125575409 is a deficient number, since it is larger than the sum of its proper divisors (1).

125575409 is an equidigital number, since it uses as much as digits as its factorization.

125575409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 63000, while the sum is 38.

The square root of 125575409 is about 11206.0434141583. The cubic root of 125575409 is about 500.7660377729.

The spelling of 125575409 in words is "one hundred twenty-five million, five hundred seventy-five thousand, four hundred nine".