12643878025 has 27 divisors (see below), whose sum is σ = 16082252199. Its totient is φ = 9860976720.

The previous prime is 12643878017. The next prime is 12643878047. The reversal of 12643878025 is 52087834621.

The square root of 12643878025 is 112445.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 4551796089 + 8092081936 = 67467^2 + 89956^2 .

It is not a de Polignac number, because 12643878025 - 2³ = 12643878017 is a prime.

It is a super-2 number, since 2×12643878025² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 24175414 + ... + 24175936.

Almost surely, 2^12643878025 is an apocalyptic number.

12643878025 is the 112445-th square number.

12643878025 is the 56223-rd centered octagonal number.

It is an amenable number.

12643878025 is a deficient number, since it is larger than the sum of its proper divisors (3438374174).

12643878025 is an frugal number, since it uses more digits than its factorization.

12643878025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1142 (or 571 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 46.

The spelling of 12643878025 in words is "twelve billion, six hundred forty-three million, eight hundred seventy-eight thousand, twenty-five".