13112112221 has 4 divisors (see below), whose sum is σ = 14120736252. Its totient is φ = 12103488192.

The previous prime is 13112112187. The next prime is 13112112239. The reversal of 13112112221 is 12221121131.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1268143321 + 11843968900 = 35611^2 + 108830^2 .

It is a cyclic number.

It is not a de Polignac number, because 13112112221 - 2⁶ = 13112112157 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13112112221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13112112271) 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, 504311996 + ... + 504312021.

It is an arithmetic number, because the mean of its divisors is an integer number (3530184063).

Almost surely, 2^13112112221 is an apocalyptic number.

It is an amenable number.

13112112221 is a deficient number, since it is larger than the sum of its proper divisors (1008624031).

13112112221 is a wasteful number, since it uses less digits than its factorization.

13112112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1008624030.

The product of its digits is 48, while the sum is 17.

Adding to 13112112221 its reverse (12221121131), we get a palindrome (25333233352).

The spelling of 13112112221 in words is "thirteen billion, one hundred twelve million, one hundred twelve thousand, two hundred twenty-one".