12543544221 has 8 divisors (see below), whose sum is σ = 18011243040. Its totient is φ = 7719104112.

The previous prime is 12543544219. The next prime is 12543544267. The reversal of 12543544221 is 12244534521.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12543544221 - 2¹ = 12543544219 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12543544271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 160814631 + ... + 160814708.

It is an arithmetic number, because the mean of its divisors is an integer number (2251405380).

Almost surely, 2^12543544221 is an apocalyptic number.

It is an amenable number.

12543544221 is a deficient number, since it is larger than the sum of its proper divisors (5467698819).

12543544221 is a wasteful number, since it uses less digits than its factorization.

12543544221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321629355.

The product of its digits is 38400, while the sum is 33.

The spelling of 12543544221 in words is "twelve billion, five hundred forty-three million, five hundred forty-four thousand, two hundred twenty-one".