231513525 has 48 divisors (see below), whose sum is σ = 440001600. Its totient is φ = 119206080.

The previous prime is 231513523. The next prime is 231513533. The reversal of 231513525 is 525315132.

It is a happy number.

It is not a de Polignac number, because 231513525 - 2¹ = 231513523 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231513521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13662 + ... + 25488.

It is an arithmetic number, because the mean of its divisors is an integer number (9166700).

Almost surely, 2^231513525 is an apocalyptic number.

231513525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

231513525 is a deficient number, since it is larger than the sum of its proper divisors (208488075).

231513525 is a wasteful number, since it uses less digits than its factorization.

231513525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11875 (or 11864 counting only the distinct ones).

The product of its digits is 4500, while the sum is 27.

The square root of 231513525 is about 15215.5685072888. The cubic root of 231513525 is about 614.0335803058.

Adding to 231513525 its reverse (525315132), we get a palindrome (756828657).

The spelling of 231513525 in words is "two hundred thirty-one million, five hundred thirteen thousand, five hundred twenty-five".