12543216551 has 4 divisors (see below), whose sum is σ = 12849148704. Its totient is φ = 12237284400.

The previous prime is 12543216541. The next prime is 12543216557. The reversal of 12543216551 is 15561234521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15561234521 = 7 ⋅2223033503.

It is a cyclic number.

It is not a de Polignac number, because 12543216551 - 2¹⁸ = 12542954407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12543216557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152966015 + ... + 152966096.

It is an arithmetic number, because the mean of its divisors is an integer number (3212287176).

Almost surely, 2^12543216551 is an apocalyptic number.

12543216551 is a deficient number, since it is larger than the sum of its proper divisors (305932153).

12543216551 is an equidigital number, since it uses as much as digits as its factorization.

12543216551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305932152.

The product of its digits is 36000, while the sum is 35.

The spelling of 12543216551 in words is "twelve billion, five hundred forty-three million, two hundred sixteen thousand, five hundred fifty-one".