99990191 has 16 divisors (see below), whose sum is σ = 116812800. Its totient is φ = 83817888.

The previous prime is 99990181. The next prime is 99990239. The reversal of 99990191 is 19109999.

It is not a de Polignac number, because 99990191 - 2¹⁸ = 99728047 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 (99990161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 98201 + ... + 99213.

It is an arithmetic number, because the mean of its divisors is an integer number (7300800).

Almost surely, 2^99990191 is an apocalyptic number.

99990191 is a deficient number, since it is larger than the sum of its proper divisors (16822609).

99990191 is a wasteful number, since it uses less digits than its factorization.

99990191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1318.

The product of its (nonzero) digits is 59049, while the sum is 47.

The square root of 99990191 is about 9999.5095379723. The cubic root of 99990191 is about 464.1437064167.

The spelling of 99990191 in words is "ninety-nine million, nine hundred ninety thousand, one hundred ninety-one".