131304221 has 2 divisors, whose sum is σ = 131304222. Its totient is φ = 131304220.

The previous prime is 131304191. The next prime is 131304233. The reversal of 131304221 is 122403131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92428996 + 38875225 = 9614^2 + 6235^2 .

It is an emirp because it is prime and its reverse (122403131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131304221 - 2¹⁸ = 131042077 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131304221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131309221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65652110 + 65652111.

It is an arithmetic number, because the mean of its divisors is an integer number (65652111).

Almost surely, 2^131304221 is an apocalyptic number.

It is an amenable number.

131304221 is a deficient number, since it is larger than the sum of its proper divisors (1).

131304221 is an equidigital number, since it uses as much as digits as its factorization.

131304221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 131304221 is about 11458.8053914882. The cubic root of 131304221 is about 508.2681497595.

Adding to 131304221 its reverse (122403131), we get a palindrome (253707352).

The spelling of 131304221 in words is "one hundred thirty-one million, three hundred four thousand, two hundred twenty-one".