91909866 has 8 divisors (see below), whose sum is σ = 183819744. Its totient is φ = 30636620.

The previous prime is 91909849. The next prime is 91909889. The reversal of 91909866 is 66890919.

It is a sphenic number, since it is the product of 3 distinct primes.

91909866 is an admirable number.

It is an unprimeable number.

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, 7659150 + ... + 7659161.

It is an arithmetic number, because the mean of its divisors is an integer number (22977468).

Almost surely, 2^91909866 is an apocalyptic number.

91909866 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91909866 is a wasteful number, since it uses less digits than its factorization.

91909866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15318316.

The product of its (nonzero) digits is 209952, while the sum is 48.

The square root of 91909866 is about 9586.9633356971. The cubic root of 91909866 is about 451.2882688927.

The spelling of 91909866 in words is "ninety-one million, nine hundred nine thousand, eight hundred sixty-six".