91091091 has 16 divisors (see below), whose sum is σ = 149483264. Its totient is φ = 48047904.

The previous prime is 91091081. The next prime is 91091129. The reversal of 91091091 is 19019019.

It is not a de Polignac number, because 91091091 - 2¹³ = 91082899 is a prime.

91091091 is a modest number, since divided by 91091 gives 91 as remainder.

It is not an unprimeable number, because it can be changed into a prime (91091041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 166561 + ... + 167106.

It is an arithmetic number, because the mean of its divisors is an integer number (9342704).

Almost surely, 2^91091091 is an apocalyptic number.

91091091 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

91091091 is a deficient number, since it is larger than the sum of its proper divisors (58392173).

91091091 is a wasteful number, since it uses less digits than its factorization.

91091091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333690.

The product of its (nonzero) digits is 729, while the sum is 30.

The square root of 91091091 is about 9544.1652856601. The cubic root of 91091091 is about 449.9441757911.

The spelling of 91091091 in words is "ninety-one million, ninety-one thousand, ninety-one".