99998191 has 2 divisors, whose sum is σ = 99998192. Its totient is φ = 99998190.

The previous prime is 99998147. The next prime is 99998207. The reversal of 99998191 is 19189999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 99998191 - 2⁹ = 99997679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99998111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49999095 + 49999096.

It is an arithmetic number, because the mean of its divisors is an integer number (49999096).

Almost surely, 2^99998191 is an apocalyptic number.

99998191 is a deficient number, since it is larger than the sum of its proper divisors (1).

99998191 is an equidigital number, since it uses as much as digits as its factorization.

99998191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 472392, while the sum is 55.

The square root of 99998191 is about 9999.9095495909. The cubic root of 99998191 is about 464.1560844663.

The spelling of 99998191 in words is "ninety-nine million, nine hundred ninety-eight thousand, one hundred ninety-one".