125405009 has 2 divisors, whose sum is σ = 125405010. Its totient is φ = 125405008.

The previous prime is 125404987. The next prime is 125405017. The reversal of 125405009 is 900504521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 90630400 + 34774609 = 9520^2 + 5897^2 .

It is a cyclic number.

It is not a de Polignac number, because 125405009 - 2²⁰ = 124356433 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (125405089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62702504 + 62702505.

It is an arithmetic number, because the mean of its divisors is an integer number (62702505).

Almost surely, 2^125405009 is an apocalyptic number.

It is an amenable number.

125405009 is a deficient number, since it is larger than the sum of its proper divisors (1).

125405009 is an equidigital number, since it uses as much as digits as its factorization.

125405009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 125405009 is about 11198.4377928352. The cubic root of 125405009 is about 500.5394298216.

The spelling of 125405009 in words is "one hundred twenty-five million, four hundred five thousand, nine".