111311131221 has 12 divisors (see below), whose sum is σ = 160933163820. Its totient is φ = 74137996800.

The previous prime is 111311131193. The next prime is 111311131249. The reversal of 111311131221 is 122131113111.

111311131221 is a `hidden beast` number, since 1 + 1 + 1 + 311 + 131 + 221 = 666.

It is an interprime number because it is at equal distance from previous prime (111311131193) and next prime (111311131249).

It can be written as a sum of positive squares in 2 ways, for example, as 82745399025 + 28565732196 = 287655^2 + 169014^2 .

It is not a de Polignac number, because 111311131221 - 2⁹ = 111311130709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111311131194 and 111311131203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111311131291) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5775180 + ... + 5794421.

It is an arithmetic number, because the mean of its divisors is an integer number (13411096985).

Almost surely, 2^111311131221 is an apocalyptic number.

It is an amenable number.

111311131221 is a deficient number, since it is larger than the sum of its proper divisors (49622032599).

111311131221 is a wasteful number, since it uses less digits than its factorization.

111311131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11570676 (or 11570673 counting only the distinct ones).

The product of its digits is 36, while the sum is 18.

Adding to 111311131221 its reverse (122131113111), we get a palindrome (233442244332).

The spelling of 111311131221 in words is "one hundred eleven billion, three hundred eleven million, one hundred thirty-one thousand, two hundred twenty-one".