1231123311 has 48 divisors (see below), whose sum is σ = 2035058688. Its totient is φ = 710424000.

The previous prime is 1231123307. The next prime is 1231123331. The reversal of 1231123311 is 1133211321.

1231123311 is a `hidden beast` number, since 1 + 231 + 123 + 311 = 666.

It is not a de Polignac number, because 1231123311 - 2² = 1231123307 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231123301) 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 47 ways as a sum of consecutive naturals, for example, 168586 + ... + 175736.

It is an arithmetic number, because the mean of its divisors is an integer number (42397056).

Almost surely, 2^1231123311 is an apocalyptic number.

1231123311 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1231123311 is a deficient number, since it is larger than the sum of its proper divisors (803935377).

1231123311 is a wasteful number, since it uses less digits than its factorization.

1231123311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7252 (or 7249 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 1231123311 is about 35087.3668291025. The cubic root of 1231123311 is about 1071.7673389486.

Adding to 1231123311 its reverse (1133211321), we get a palindrome (2364334632).

The spelling of 1231123311 in words is "one billion, two hundred thirty-one million, one hundred twenty-three thousand, three hundred eleven".