98199991 has 2 divisors, whose sum is σ = 98199992. Its totient is φ = 98199990.

The previous prime is 98199989. The next prime is 98200001. The reversal of 98199991 is 19999189.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 98199991 - 2¹ = 98199989 is a prime.

Together with 98199989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (98199901) 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, 49099995 + 49099996.

It is an arithmetic number, because the mean of its divisors is an integer number (49099996).

Almost surely, 2^98199991 is an apocalyptic number.

98199991 is a deficient number, since it is larger than the sum of its proper divisors (1).

98199991 is an equidigital number, since it uses as much as digits as its factorization.

98199991 is an odious number, because the sum of its binary digits is odd.

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

The square root of 98199991 is about 9909.5908593645. The cubic root of 98199991 is about 461.3570371177.

The spelling of 98199991 in words is "ninety-eight million, one hundred ninety-nine thousand, nine hundred ninety-one".