1213311331 has 4 divisors (see below), whose sum is σ = 1213382664. Its totient is φ = 1213240000.

The previous prime is 1213311317. The next prime is 1213311343. The reversal of 1213311331 is 1331133121.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1331133121 = 937 ⋅1420633.

It is a cyclic number.

It is not a de Polignac number, because 1213311331 - 2¹³ = 1213303139 is a prime.

It is a super-2 number, since 2×1213311331² = 2944248771865983122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1213311299 and 1213311308.

It is not an unprimeable number, because it can be changed into a prime (1213311371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6336 + ... + 49666.

It is an arithmetic number, because the mean of its divisors is an integer number (303345666).

Almost surely, 2^1213311331 is an apocalyptic number.

1213311331 is a deficient number, since it is larger than the sum of its proper divisors (71333).

1213311331 is an equidigital number, since it uses as much as digits as its factorization.

1213311331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71332.

The product of its digits is 162, while the sum is 19.

The square root of 1213311331 is about 34832.6187789549. The cubic root of 1213311331 is about 1066.5734069615.

Adding to 1213311331 its reverse (1331133121), we get a palindrome (2544444452).

The spelling of 1213311331 in words is "one billion, two hundred thirteen million, three hundred eleven thousand, three hundred thirty-one".