1231101311 has 12 divisors (see below), whose sum is σ = 1368410400. Its totient is φ = 1106598240.

The previous prime is 1231101307. The next prime is 1231101341. The reversal of 1231101311 is 1131011321.

It is a happy number.

It is not a de Polignac number, because 1231101311 - 2² = 1231101307 is a prime.

It is a super-2 number, since 2×1231101311² = 3031220875891837442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231101341) 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 11 ways as a sum of consecutive naturals, for example, 46391 + ... + 67928.

It is an arithmetic number, because the mean of its divisors is an integer number (114034200).

Almost surely, 2^1231101311 is an apocalyptic number.

1231101311 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1231101311 is a deficient number, since it is larger than the sum of its proper divisors (137309089).

1231101311 is a wasteful number, since it uses less digits than its factorization.

1231101311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114430 (or 114419 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 1231101311 is about 35087.0533245526. The cubic root of 1231101311 is about 1071.7609548001.

Adding to 1231101311 its reverse (1131011321), we get a palindrome (2362112632).

It can be divided in two parts, 123110 and 1311, that added together give a palindrome (124421).

The spelling of 1231101311 in words is "one billion, two hundred thirty-one million, one hundred one thousand, three hundred eleven".