221311112121 has 48 divisors (see below), whose sum is σ = 372514334400. Its totient is φ = 125120808960.

The previous prime is 221311112083. The next prime is 221311112131. The reversal of 221311112121 is 121211113122.

It is a happy number.

221311112121 is a `hidden beast` number, since 221 + 311 + 1 + 12 + 121 = 666.

It is not a de Polignac number, because 221311112121 - 2²² = 221306917817 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221311112094 and 221311112103.

It is not an unprimeable number, because it can be changed into a prime (221311112131) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 391671 + ... + 772028.

It is an arithmetic number, because the mean of its divisors is an integer number (7760715300).

Almost surely, 2^221311112121 is an apocalyptic number.

It is an amenable number.

221311112121 is a deficient number, since it is larger than the sum of its proper divisors (151203222279).

221311112121 is a wasteful number, since it uses less digits than its factorization.

221311112121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1163846 (or 1163843 counting only the distinct ones).

The product of its digits is 48, while the sum is 18.

Adding to 221311112121 its reverse (121211113122), we get a palindrome (342522225243).

The spelling of 221311112121 in words is "two hundred twenty-one billion, three hundred eleven million, one hundred twelve thousand, one hundred twenty-one".