9855498221 has 2 divisors, whose sum is σ = 9855498222. Its totient is φ = 9855498220.

The previous prime is 9855498217. The next prime is 9855498253. The reversal of 9855498221 is 1228945589.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9689449225 + 166048996 = 98435^2 + 12886^2 .

It is a cyclic number.

It is not a de Polignac number, because 9855498221 - 2² = 9855498217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9855498421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4927749110 + 4927749111.

It is an arithmetic number, because the mean of its divisors is an integer number (4927749111).

Almost surely, 2^9855498221 is an apocalyptic number.

It is an amenable number.

9855498221 is a deficient number, since it is larger than the sum of its proper divisors (1).

9855498221 is an equidigital number, since it uses as much as digits as its factorization.

9855498221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2073600, while the sum is 53.

The square root of 9855498221 is about 99274.8619792543. The cubic root of 9855498221 is about 2144.0069786247.

The spelling of 9855498221 in words is "nine billion, eight hundred fifty-five million, four hundred ninety-eight thousand, two hundred twenty-one".