131312821 has 2 divisors, whose sum is σ = 131312822. Its totient is φ = 131312820.

The previous prime is 131312801. The next prime is 131312837. The reversal of 131312821 is 128213131.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 83010321 + 48302500 = 9111^2 + 6950^2 .

It is an emirp because it is prime and its reverse (128213131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131312821 - 2⁷ = 131312693 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131312792 and 131312801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131312801) 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 as a sum of consecutive naturals, namely, 65656410 + 65656411.

It is an arithmetic number, because the mean of its divisors is an integer number (65656411).

Almost surely, 2^131312821 is an apocalyptic number.

It is an amenable number.

131312821 is a deficient number, since it is larger than the sum of its proper divisors (1).

131312821 is an equidigital number, since it uses as much as digits as its factorization.

131312821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 288, while the sum is 22.

The square root of 131312821 is about 11459.1806426114. The cubic root of 131312821 is about 508.2792461549.

Adding to 131312821 its reverse (128213131), we get a palindrome (259525952).

The spelling of 131312821 in words is "one hundred thirty-one million, three hundred twelve thousand, eight hundred twenty-one".