11312311221 has 6 divisors (see below), whose sum is σ = 16340005110. Its totient is φ = 7541540808.

The previous prime is 11312311211. The next prime is 11312311243. The reversal of 11312311221 is 12211321311.

11312311221 is a `hidden beast` number, since 1 + 131 + 2 + 311 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 8951808996 + 2360502225 = 94614^2 + 48585^2 .

It is not a de Polignac number, because 11312311221 - 2⁷ = 11312311093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11312311194 and 11312311203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11312311211) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 628461726 + ... + 628461743.

It is an arithmetic number, because the mean of its divisors is an integer number (2723334185).

Almost surely, 2^11312311221 is an apocalyptic number.

It is an amenable number.

11312311221 is a deficient number, since it is larger than the sum of its proper divisors (5027693889).

11312311221 is a wasteful number, since it uses less digits than its factorization.

11312311221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1256923475 (or 1256923472 counting only the distinct ones).

The product of its digits is 72, while the sum is 18.

Adding to 11312311221 its reverse (12211321311), we get a palindrome (23523632532).

The spelling of 11312311221 in words is "eleven billion, three hundred twelve million, three hundred eleven thousand, two hundred twenty-one".