12525442221 has 4 divisors (see below), whose sum is σ = 16700589632. Its totient is φ = 8350294812.

The previous prime is 12525442217. The next prime is 12525442243. The reversal of 12525442221 is 12224452521.

12525442221 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 not a de Polignac number, because 12525442221 - 2² = 12525442217 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 (12525442261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2087573701 + ... + 2087573706.

It is an arithmetic number, because the mean of its divisors is an integer number (4175147408).

Almost surely, 2^12525442221 is an apocalyptic number.

It is an amenable number.

12525442221 is a deficient number, since it is larger than the sum of its proper divisors (4175147411).

12525442221 is an equidigital number, since it uses as much as digits as its factorization.

12525442221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4175147410.

The product of its digits is 12800, while the sum is 30.

Adding to 12525442221 its reverse (12224452521), we get a palindrome (24749894742).

The spelling of 12525442221 in words is "twelve billion, five hundred twenty-five million, four hundred forty-two thousand, two hundred twenty-one".