221543121213 has 12 divisors (see below), whose sum is σ = 320018792028. Its totient is φ = 147689847360.

The previous prime is 221543121193. The next prime is 221543121251. The reversal of 221543121213 is 312121345122.

It is a happy number.

221543121213 is a `hidden beast` number, since 2 + 2 + 1 + 5 + 431 + 212 + 13 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 185565377529 + 35977743684 = 430773^2 + 189678^2 .

It is not a de Polignac number, because 221543121213 - 2¹⁴ = 221543104829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221543121013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 204198 + ... + 696263.

It is an arithmetic number, because the mean of its divisors is an integer number (26668232669).

Almost surely, 2^221543121213 is an apocalyptic number.

It is an amenable number.

221543121213 is a deficient number, since it is larger than the sum of its proper divisors (98475670815).

221543121213 is a wasteful number, since it uses less digits than its factorization.

221543121213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 927804 (or 927801 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

Adding to 221543121213 its reverse (312121345122), we get a palindrome (533664466335).

The spelling of 221543121213 in words is "two hundred twenty-one billion, five hundred forty-three million, one hundred twenty-one thousand, two hundred thirteen".