12520661 has 4 divisors (see below), whose sum is σ = 12528000. Its totient is φ = 12513324.

The previous prime is 12520657. The next prime is 12520691. The reversal of 12520661 is 16602521.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 12520661 - 2² = 12520657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12520691) 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, 380 + ... + 5018.

It is an arithmetic number, because the mean of its divisors is an integer number (3132000).

Almost surely, 2^12520661 is an apocalyptic number.

It is an amenable number.

12520661 is a deficient number, since it is larger than the sum of its proper divisors (7339).

12520661 is an equidigital number, since it uses as much as digits as its factorization.

12520661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7338.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 12520661 is about 3538.4546061805. The cubic root of 12520661 is about 232.2072377851.

The spelling of 12520661 in words is "twelve million, five hundred twenty thousand, six hundred sixty-one".