12165561325 has 12 divisors (see below), whose sum is σ = 15291946228. Its totient is φ = 9599126400.

The previous prime is 12165561323. The next prime is 12165561337. The reversal of 12165561325 is 52316556121.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 89529444 + 12076031881 = 9462^2 + 109891^2 .

It is not a de Polignac number, because 12165561325 - 2¹ = 12165561323 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 (12165561323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3331206 + ... + 3334855.

Almost surely, 2^12165561325 is an apocalyptic number.

It is an amenable number.

12165561325 is a deficient number, since it is larger than the sum of its proper divisors (3126384903).

12165561325 is an equidigital number, since it uses as much as digits as its factorization.

12165561325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6666144 (or 6666139 counting only the distinct ones).

The product of its digits is 54000, while the sum is 37.

The spelling of 12165561325 in words is "twelve billion, one hundred sixty-five million, five hundred sixty-one thousand, three hundred twenty-five".