1211123203111 has 2 divisors, whose sum is σ = 1211123203112. Its totient is φ = 1211123203110.

The previous prime is 1211123203033. The next prime is 1211123203127. The reversal of 1211123203111 is 1113023211121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1211123203111 - 2⁷ = 1211123202983 is a prime.

It is a super-2 number, since 2×1211123203111² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211123203151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605561601555 + 605561601556.

It is an arithmetic number, because the mean of its divisors is an integer number (605561601556).

Almost surely, 2^{1211123203111} is an apocalyptic number.

1211123203111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211123203111 is an equidigital number, since it uses as much as digits as its factorization.

1211123203111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 19.

Adding to 1211123203111 its reverse (1113023211121), we get a palindrome (2324146414232).

The spelling of 1211123203111 in words is "one trillion, two hundred eleven billion, one hundred twenty-three million, two hundred three thousand, one hundred eleven".