91989394 has 16 divisors (see below), whose sum is σ = 157856256. Its totient is φ = 39384000.

The previous prime is 91989389. The next prime is 91989409. The reversal of 91989394 is 49398919.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14079 + ... + 19549.

It is an arithmetic number, because the mean of its divisors is an integer number (9866016).

Almost surely, 2^91989394 is an apocalyptic number.

91989394 is a deficient number, since it is larger than the sum of its proper divisors (65866862).

91989394 is a wasteful number, since it uses less digits than its factorization.

91989394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6681.

The product of its digits is 629856, while the sum is 52.

The square root of 91989394 is about 9591.1101547214. The cubic root of 91989394 is about 451.4183953173.

The spelling of 91989394 in words is "ninety-one million, nine hundred eighty-nine thousand, three hundred ninety-four".