231125809509 has 16 divisors (see below), whose sum is σ = 391324122240. Its totient is φ = 132071891040.

The previous prime is 231125809507. The next prime is 231125809513. The reversal of 231125809509 is 905908521132.

231125809509 is a `hidden beast` number, since 2 + 3 + 1 + 12 + 580 + 9 + 50 + 9 = 666.

It is not a de Polignac number, because 231125809509 - 2¹ = 231125809507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231125809507) 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, 611443752 + ... + 611444129.

It is an arithmetic number, because the mean of its divisors is an integer number (24457757640).

Almost surely, 2^231125809509 is an apocalyptic number.

It is an amenable number.

231125809509 is a deficient number, since it is larger than the sum of its proper divisors (160198312731).

231125809509 is a wasteful number, since it uses less digits than its factorization.

231125809509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1222887897 (or 1222887891 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The spelling of 231125809509 in words is "two hundred thirty-one billion, one hundred twenty-five million, eight hundred nine thousand, five hundred nine".