1211331331123 has 4 divisors (see below), whose sum is σ = 1211811830008. Its totient is φ = 1210850832240.

The previous prime is 1211331331103. The next prime is 1211331331151. The reversal of 1211331331123 is 3211331331121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211331331123 is a prime.

It is a super-2 number, since 2×1211331331123² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211331331103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 240245661 + ... + 240250702.

It is an arithmetic number, because the mean of its divisors is an integer number (302952957502).

Almost surely, 2^{1211331331123} is an apocalyptic number.

1211331331123 is a deficient number, since it is larger than the sum of its proper divisors (480498885).

1211331331123 is an equidigital number, since it uses as much as digits as its factorization.

1211331331123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480498884.

The product of its digits is 972, while the sum is 25.

Adding to 1211331331123 its reverse (3211331331121), we get a palindrome (4422662662244).

The spelling of 1211331331123 in words is "one trillion, two hundred eleven billion, three hundred thirty-one million, three hundred thirty-one thousand, one hundred twenty-three".