12511221525 has 90 divisors (see below), whose sum is σ = 25473963746. Its totient is φ = 6065928000.

The previous prime is 12511221523. The next prime is 12511221539. The reversal of 12511221525 is 52512211521.

12511221525 is a `hidden beast` number, since 1 + 2 + 5 + 112 + 21 + 525 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 84768849 + 12426452676 = 9207^2 + 111474^2 .

It is not a de Polignac number, because 12511221525 - 2¹ = 12511221523 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12511221523) by changing a digit.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 219495 + ... + 270555.

Almost surely, 2^12511221525 is an apocalyptic number.

12511221525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12511221525 is an abundant number, since it is smaller than the sum of its proper divisors (12962742221).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12511221525 is a wasteful number, since it uses less digits than its factorization.

12511221525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51105 (or 51080 counting only the distinct ones).

The product of its digits is 2000, while the sum is 27.

The spelling of 12511221525 in words is "twelve billion, five hundred eleven million, two hundred twenty-one thousand, five hundred twenty-five".