1231321231 has 16 divisors (see below), whose sum is σ = 1415887360. Its totient is φ = 1048943520.

The previous prime is 1231321219. The next prime is 1231321253. The reversal of 1231321231 is 1321231321.

It is a cyclic number.

It is not a de Polignac number, because 1231321231 - 2⁷ = 1231321103 is a prime.

It is a super-2 number, since 2×1231321231² = 3032303947822710722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1231321199 and 1231321208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231322231) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1339390 + ... + 1340308.

It is an arithmetic number, because the mean of its divisors is an integer number (88492960).

Almost surely, 2^1231321231 is an apocalyptic number.

1231321231 is a deficient number, since it is larger than the sum of its proper divisors (184566129).

1231321231 is an equidigital number, since it uses as much as digits as its factorization.

1231321231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1894.

The product of its digits is 216, while the sum is 19.

The square root of 1231321231 is about 35090.1871040894. The cubic root of 1231321231 is about 1071.8247696499.

Adding to 1231321231 its reverse (1321231321), we get a palindrome (2552552552).

The spelling of 1231321231 in words is "one billion, two hundred thirty-one million, three hundred twenty-one thousand, two hundred thirty-one".