131663221 has 2 divisors, whose sum is σ = 131663222. Its totient is φ = 131663220.

The previous prime is 131663167. The next prime is 131663237. The reversal of 131663221 is 122366131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76755121 + 54908100 = 8761^2 + 7410^2 .

It is an emirp because it is prime and its reverse (122366131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131663221 - 2⁷ = 131663093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131663281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65831610 + 65831611.

It is an arithmetic number, because the mean of its divisors is an integer number (65831611).

Almost surely, 2^131663221 is an apocalyptic number.

It is an amenable number.

131663221 is a deficient number, since it is larger than the sum of its proper divisors (1).

131663221 is an equidigital number, since it uses as much as digits as its factorization.

131663221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 25.

The square root of 131663221 is about 11474.4595079681. The cubic root of 131663221 is about 508.7309483415.

The spelling of 131663221 in words is "one hundred thirty-one million, six hundred sixty-three thousand, two hundred twenty-one".