1311221133 has 24 divisors (see below), whose sum is σ = 1978173600. Its totient is φ = 836093664.

The previous prime is 1311221111. The next prime is 1311221143. The reversal of 1311221133 is 3311221131.

1311221133 is a `hidden beast` number, since 1 + 311 + 221 + 133 = 666.

It is not a de Polignac number, because 1311221133 - 2¹⁶ = 1311155597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311221143) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13723 + ... + 53016.

It is an arithmetic number, because the mean of its divisors is an integer number (82423900).

Almost surely, 2^1311221133 is an apocalyptic number.

It is an amenable number.

1311221133 is a deficient number, since it is larger than the sum of its proper divisors (666952467).

1311221133 is a wasteful number, since it uses less digits than its factorization.

1311221133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66841 (or 66838 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 1311221133 is about 36210.7875225049. The cubic root of 1311221133 is about 1094.5240616330.

Adding to 1311221133 its reverse (3311221131), we get a palindrome (4622442264).

The spelling of 1311221133 in words is "one billion, three hundred eleven million, two hundred twenty-one thousand, one hundred thirty-three".