90858221 has 2 divisors, whose sum is σ = 90858222. Its totient is φ = 90858220.

The previous prime is 90858197. The next prime is 90858227. The reversal of 90858221 is 12285809.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60762025 + 30096196 = 7795^2 + 5486^2 .

It is an emirp because it is prime and its reverse (12285809) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90858221 - 2¹⁴ = 90841837 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90858227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45429110 + 45429111.

It is an arithmetic number, because the mean of its divisors is an integer number (45429111).

Almost surely, 2^90858221 is an apocalyptic number.

It is an amenable number.

90858221 is a deficient number, since it is larger than the sum of its proper divisors (1).

90858221 is an equidigital number, since it uses as much as digits as its factorization.

90858221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11520, while the sum is 35.

The square root of 90858221 is about 9531.9578786312. The cubic root of 90858221 is about 449.5604283680.

The spelling of 90858221 in words is "ninety million, eight hundred fifty-eight thousand, two hundred twenty-one".