1231211123 has 2 divisors, whose sum is σ = 1231211124. Its totient is φ = 1231211122.

The previous prime is 1231211119. The next prime is 1231211161. The reversal of 1231211123 is 3211121321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1231211123 - 2² = 1231211119 is a prime.

It is a super-2 number, since 2×1231211123² = 3031761658797842258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1231201123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615605561 + 615605562.

It is an arithmetic number, because the mean of its divisors is an integer number (615605562).

Almost surely, 2^1231211123 is an apocalyptic number.

1231211123 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231211123 is an equidigital number, since it uses as much as digits as its factorization.

1231211123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72, while the sum is 17.

The square root of 1231211123 is about 35088.6181403600. The cubic root of 1231211123 is about 1071.7928202293.

Adding to 1231211123 its reverse (3211121321), we get a palindrome (4442332444).

The spelling of 1231211123 in words is "one billion, two hundred thirty-one million, two hundred eleven thousand, one hundred twenty-three".