1221131111323 has 2 divisors, whose sum is σ = 1221131111324. Its totient is φ = 1221131111322.

The previous prime is 1221131111311. The next prime is 1221131111383. The reversal of 1221131111323 is 3231111311221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221131111323 - 2⁹ = 1221131110811 is a prime.

It is a super-2 number, since 2×1221131111323² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221131111294 and 1221131111303.

It is not a weakly prime, because it can be changed into another prime (1221131111383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610565555661 + 610565555662.

It is an arithmetic number, because the mean of its divisors is an integer number (610565555662).

Almost surely, 2^{1221131111323} is an apocalyptic number.

1221131111323 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221131111323 is an equidigital number, since it uses as much as digits as its factorization.

1221131111323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 216, while the sum is 22.

Adding to 1221131111323 its reverse (3231111311221), we get a palindrome (4452242422544).

The spelling of 1221131111323 in words is "one trillion, two hundred twenty-one billion, one hundred thirty-one million, one hundred eleven thousand, three hundred twenty-three".