125553309 has 16 divisors (see below), whose sum is σ = 195391488. Its totient is φ = 70217712.

The previous prime is 125553301. The next prime is 125553319. The reversal of 125553309 is 903355521.

It is not a de Polignac number, because 125553309 - 2³ = 125553301 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 125553309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125553301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62617 + ... + 64590.

It is an arithmetic number, because the mean of its divisors is an integer number (12211968).

Almost surely, 2^125553309 is an apocalyptic number.

It is an amenable number.

125553309 is a deficient number, since it is larger than the sum of its proper divisors (69838179).

125553309 is a wasteful number, since it uses less digits than its factorization.

125553309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127264.

The product of its (nonzero) digits is 20250, while the sum is 33.

The square root of 125553309 is about 11205.0572957036. The cubic root of 125553309 is about 500.7366594660.

The spelling of 125553309 in words is "one hundred twenty-five million, five hundred fifty-three thousand, three hundred nine".