12551821551025 has 27 divisors (see below), whose sum is σ = 15755884803841. Its totient is φ = 9919313771840.

The previous prime is 12551821551011. The next prime is 12551821551037. The reversal of 12551821551025 is 52015512815521.

The square root of 12551821551025 is 3542855.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1063870536481 + 11487951014544 = 1031441^2 + 3389388^2 .

It is not a de Polignac number, because 12551821551025 - 2⁷ = 12551821550897 is a prime.

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, 1470280557 + ... + 1470289093.

Almost surely, 2^{12551821551025} is an apocalyptic number.

12551821551025 is the 3542855-th square number.

12551821551025 is the 1771428-th centered octagonal number.

It is an amenable number.

12551821551025 is a deficient number, since it is larger than the sum of its proper divisors (3204063252816).

12551821551025 is an frugal number, since it uses more digits than its factorization.

12551821551025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17250 (or 8625 counting only the distinct ones).

The product of its (nonzero) digits is 200000, while the sum is 43.

The spelling of 12551821551025 in words is "twelve trillion, five hundred fifty-one billion, eight hundred twenty-one million, five hundred fifty-one thousand, twenty-five".