231521012 has 12 divisors (see below), whose sum is σ = 405313860. Its totient is φ = 115717056.

The previous prime is 231521009. The next prime is 231521021. The reversal of 231521012 is 210125132.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 146991376 + 84529636 = 12124^2 + 9194^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 3128 + ... + 21744.

It is an arithmetic number, because the mean of its divisors is an integer number (33776155).

Almost surely, 2^231521012 is an apocalyptic number.

It is an amenable number.

231521012 is a deficient number, since it is larger than the sum of its proper divisors (173792848).

231521012 is a wasteful number, since it uses less digits than its factorization.

231521012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21730 (or 21728 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 231521012 is about 15215.8145361988. The cubic root of 231521012 is about 614.0401993861.

Adding to 231521012 its reverse (210125132), we get a palindrome (441646144).

The spelling of 231521012 in words is "two hundred thirty-one million, five hundred twenty-one thousand, twelve".