12031521 has 4 divisors (see below), whose sum is σ = 16042032. Its totient is φ = 8021012.

The previous prime is 12031517. The next prime is 12031543. The reversal of 12031521 is 12513021.

12031521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12031521 - 2² = 12031517 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 12031521.

It is not an unprimeable number, because it can be changed into a prime (12031561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2005251 + ... + 2005256.

It is an arithmetic number, because the mean of its divisors is an integer number (4010508).

Almost surely, 2^12031521 is an apocalyptic number.

It is an amenable number.

12031521 is a deficient number, since it is larger than the sum of its proper divisors (4010511).

12031521 is an equidigital number, since it uses as much as digits as its factorization.

12031521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4010510.

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 12031521 is about 3468.6482958063. The cubic root of 12031521 is about 229.1431317906.

Adding to 12031521 its reverse (12513021), we get a palindrome (24544542).

The spelling of 12031521 in words is "twelve million, thirty-one thousand, five hundred twenty-one".