99198391 has 4 divisors (see below), whose sum is σ = 100679032. Its totient is φ = 97717752.

The previous prime is 99198371. The next prime is 99198397. The reversal of 99198391 is 19389199.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 99198391 - 2⁷ = 99198263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99198397) 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 in 3 ways as a sum of consecutive naturals, for example, 740220 + ... + 740353.

It is an arithmetic number, because the mean of its divisors is an integer number (25169758).

Almost surely, 2^99198391 is an apocalyptic number.

99198391 is a deficient number, since it is larger than the sum of its proper divisors (1480641).

99198391 is a wasteful number, since it uses less digits than its factorization.

99198391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1480640.

The product of its digits is 157464, while the sum is 49.

The square root of 99198391 is about 9959.8389043197. The cubic root of 99198391 is about 462.9153080867.

The spelling of 99198391 in words is "ninety-nine million, one hundred ninety-eight thousand, three hundred ninety-one".