12543421403 has 4 divisors (see below), whose sum is σ = 12571736568. Its totient is φ = 12515106240.

The previous prime is 12543421343. The next prime is 12543421421. The reversal of 12543421403 is 30412434521.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12543421403 - 2³⁰ = 11469679579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12543421433) 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, 14156918 + ... + 14157803.

It is an arithmetic number, because the mean of its divisors is an integer number (3142934142).

Almost surely, 2^12543421403 is an apocalyptic number.

12543421403 is a deficient number, since it is larger than the sum of its proper divisors (28315165).

12543421403 is an equidigital number, since it uses as much as digits as its factorization.

12543421403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28315164.

The product of its (nonzero) digits is 11520, while the sum is 29.

Adding to 12543421403 its reverse (30412434521), we get a palindrome (42955855924).

The spelling of 12543421403 in words is "twelve billion, five hundred forty-three million, four hundred twenty-one thousand, four hundred three".