12007521 has 20 divisors (see below), whose sum is σ = 18282132. Its totient is φ = 7851168.

The previous prime is 12007519. The next prime is 12007529. The reversal of 12007521 is 12570021.

12007521 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 8767521 + 3240000 = 2961^2 + 1800^2 .

It is not a de Polignac number, because 12007521 - 2¹ = 12007519 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12007494 and 12007503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12007529) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2895 + ... + 5691.

Almost surely, 2^12007521 is an apocalyptic number.

It is an amenable number.

12007521 is a deficient number, since it is larger than the sum of its proper divisors (6274611).

12007521 is an equidigital number, since it uses as much as digits as its factorization.

12007521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2862 (or 2853 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 12007521 is about 3465.1870079406. The cubic root of 12007521 is about 228.9906684984.

Adding to 12007521 its reverse (12570021), we get a palindrome (24577542).

Subtracting 12007521 from its reverse (12570021), we obtain a square (562500 = 750²).

The spelling of 12007521 in words is "twelve million, seven thousand, five hundred twenty-one".