12543975551 has 4 divisors (see below), whose sum is σ = 12549496512. Its totient is φ = 12538454592.

The previous prime is 12543975533. The next prime is 12543975557. The reversal of 12543975551 is 15557934521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15557934521 = 19 ⋅818838659.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12543975551 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12543975496 and 12543975505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12543975557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2757071 + ... + 2761616.

It is an arithmetic number, because the mean of its divisors is an integer number (3137374128).

Almost surely, 2^12543975551 is an apocalyptic number.

12543975551 is a deficient number, since it is larger than the sum of its proper divisors (5520961).

12543975551 is an equidigital number, since it uses as much as digits as its factorization.

12543975551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5520960.

The product of its digits is 945000, while the sum is 47.

The spelling of 12543975551 in words is "twelve billion, five hundred forty-three million, nine hundred seventy-five thousand, five hundred fifty-one".