12645553 has 4 divisors (see below), whose sum is σ = 12711268. Its totient is φ = 12579840.

The previous prime is 12645547. The next prime is 12645623. The reversal of 12645553 is 35554621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35554621 = 3463 ⋅10267.

It can be written as a sum of positive squares in 2 ways, for example, as 5094049 + 7551504 = 2257^2 + 2748^2 .

It is a cyclic number.

It is not a de Polignac number, because 12645553 - 2⁹ = 12645041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12645533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32568 + ... + 32953.

It is an arithmetic number, because the mean of its divisors is an integer number (3177817).

Almost surely, 2^12645553 is an apocalyptic number.

It is an amenable number.

12645553 is a deficient number, since it is larger than the sum of its proper divisors (65715).

12645553 is an equidigital number, since it uses as much as digits as its factorization.

12645553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65714.

The product of its digits is 18000, while the sum is 31.

The square root of 12645553 is about 3556.0586328125. The cubic root of 12645553 is about 232.9767640014.

The spelling of 12645553 in words is "twelve million, six hundred forty-five thousand, five hundred fifty-three".