12505021 has 4 divisors (see below), whose sum is σ = 13163200. Its totient is φ = 11846844.

The previous prime is 12504977. The next prime is 12505037. The reversal of 12505021 is 12050521.

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 a de Polignac number, because none of the positive numbers 2^k-12505021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12504986 and 12505004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12505091) 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, 329061 + ... + 329098.

It is an arithmetic number, because the mean of its divisors is an integer number (3290800).

Almost surely, 2^12505021 is an apocalyptic number.

It is an amenable number.

12505021 is a deficient number, since it is larger than the sum of its proper divisors (658179).

12505021 is an equidigital number, since it uses as much as digits as its factorization.

12505021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 658178.

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 12505021 is about 3536.2439112708. The cubic root of 12505021 is about 232.1105114110.

Adding to 12505021 its reverse (12050521), we get a palindrome (24555542).

The spelling of 12505021 in words is "twelve million, five hundred five thousand, twenty-one".