131231213 has 2 divisors, whose sum is σ = 131231214. Its totient is φ = 131231212.

The previous prime is 131231207. The next prime is 131231237. The reversal of 131231213 is 312132131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130462084 + 769129 = 11422^2 + 877^2 .

It is a cyclic number.

It is not a de Polignac number, because 131231213 - 2¹⁰ = 131230189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131231191 and 131231200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131231273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65615606 + 65615607.

It is an arithmetic number, because the mean of its divisors is an integer number (65615607).

Almost surely, 2^131231213 is an apocalyptic number.

It is an amenable number.

131231213 is a deficient number, since it is larger than the sum of its proper divisors (1).

131231213 is an equidigital number, since it uses as much as digits as its factorization.

131231213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108, while the sum is 17.

The square root of 131231213 is about 11455.6192761457. The cubic root of 131231213 is about 508.1739295827.

Adding to 131231213 its reverse (312132131), we get a palindrome (443363344).

The spelling of 131231213 in words is "one hundred thirty-one million, two hundred thirty-one thousand, two hundred thirteen".