12231521 has 2 divisors, whose sum is σ = 12231522. Its totient is φ = 12231520.

The previous prime is 12231511. The next prime is 12231523. The reversal of 12231521 is 12513221.

It is a happy number.

12231521 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9541921 + 2689600 = 3089^2 + 1640^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12231521 is a prime.

It is a super-2 number, since 2×12231521² = 299220211946882, which contains 22 as substring.

Together with 12231523, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12231521.

It is not a weakly prime, because it can be changed into another prime (12231523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6115760 + 6115761.

It is an arithmetic number, because the mean of its divisors is an integer number (6115761).

Almost surely, 2^12231521 is an apocalyptic number.

It is an amenable number.

12231521 is a deficient number, since it is larger than the sum of its proper divisors (1).

12231521 is an equidigital number, since it uses as much as digits as its factorization.

12231521 is an evil number, because the sum of its binary digits is even.

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

The square root of 12231521 is about 3497.3591465562. The cubic root of 12231521 is about 230.4058430010.

Adding to 12231521 its reverse (12513221), we get a palindrome (24744742).

It can be divided in two parts, 1223 and 1521, that added together give a cube (2744 = 14³).

The spelling of 12231521 in words is "twelve million, two hundred thirty-one thousand, five hundred twenty-one".