125931909 has 8 divisors (see below), whose sum is σ = 168643360. Its totient is φ = 83587536.

The previous prime is 125931853. The next prime is 125931913. The reversal of 125931909 is 909139521.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 125931909 - 2⁷ = 125931781 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125931959) 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 in 7 ways as a sum of consecutive naturals, for example, 90967 + ... + 92340.

It is an arithmetic number, because the mean of its divisors is an integer number (21080420).

Almost surely, 2^125931909 is an apocalyptic number.

It is an amenable number.

125931909 is a deficient number, since it is larger than the sum of its proper divisors (42711451).

125931909 is a wasteful number, since it uses less digits than its factorization.

125931909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183539.

The product of its (nonzero) digits is 21870, while the sum is 39.

The square root of 125931909 is about 11221.9387362434. The cubic root of 125931909 is about 501.2394702216.

The spelling of 125931909 in words is "one hundred twenty-five million, nine hundred thirty-one thousand, nine hundred nine".