99543221 has 2 divisors, whose sum is σ = 99543222. Its totient is φ = 99543220.

The previous prime is 99543187. The next prime is 99543233. The reversal of 99543221 is 12234599.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88078225 + 11464996 = 9385^2 + 3386^2 .

It is a cyclic number.

It is not a de Polignac number, because 99543221 - 2¹⁴ = 99526837 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99543251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49771610 + 49771611.

It is an arithmetic number, because the mean of its divisors is an integer number (49771611).

Almost surely, 2^99543221 is an apocalyptic number.

It is an amenable number.

99543221 is a deficient number, since it is larger than the sum of its proper divisors (1).

99543221 is an equidigital number, since it uses as much as digits as its factorization.

99543221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 35.

The square root of 99543221 is about 9977.1349093816. The cubic root of 99543221 is about 463.4510777938.

The spelling of 99543221 in words is "ninety-nine million, five hundred forty-three thousand, two hundred twenty-one".