12618253561 has 3 divisors (see below), whose sum is σ = 12618365893. Its totient is φ = 12618141230.

The previous prime is 12618253541. The next prime is 12618253573. The reversal of 12618253561 is 16535281621.

The square root of 12618253561 is 112331.

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

12618253561 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 brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 12618253561 - 2¹³ = 12618245369 is a prime.

It is a super-4 number, since 4×12618253561⁴ (a number of 42 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12618253541) 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 2 ways as a sum of consecutive naturals, for example, 56166 + ... + 168496.

Almost surely, 2^12618253561 is an apocalyptic number.

12618253561 is the 112331-st square number.

12618253561 is the 56166-th centered octagonal number.

It is an amenable number.

12618253561 is a deficient number, since it is larger than the sum of its proper divisors (112332).

12618253561 is an frugal number, since it uses more digits than its factorization.

12618253561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224662 (or 112331 counting only the distinct ones).

The product of its digits is 86400, while the sum is 40.

The spelling of 12618253561 in words is "twelve billion, six hundred eighteen million, two hundred fifty-three thousand, five hundred sixty-one".