90606221 has 2 divisors, whose sum is σ = 90606222. Its totient is φ = 90606220.

The previous prime is 90606181. The next prime is 90606227. The reversal of 90606221 is 12260609.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 90060100 + 546121 = 9490^2 + 739^2 .

It is a cyclic number.

It is not a de Polignac number, because 90606221 - 2¹⁰ = 90605197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90606227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45303110 + 45303111.

It is an arithmetic number, because the mean of its divisors is an integer number (45303111).

Almost surely, 2^90606221 is an apocalyptic number.

It is an amenable number.

90606221 is a deficient number, since it is larger than the sum of its proper divisors (1).

90606221 is an equidigital number, since it uses as much as digits as its factorization.

90606221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 90606221 is about 9518.7300098280. The cubic root of 90606221 is about 449.1444171136.

The spelling of 90606221 in words is "ninety million, six hundred six thousand, two hundred twenty-one".