91005109 has 8 divisors (see below), whose sum is σ = 99017240. Its totient is φ = 83137536.

The previous prime is 91005091. The next prime is 91005143. The reversal of 91005109 is 90150019.

It can be written as a sum of positive squares in 4 ways, for example, as 850084 + 90155025 = 922^2 + 9495^2 .

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

It is not a de Polignac number, because 91005109 - 2¹¹ = 91003061 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 (91005149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34824 + ... + 37345.

It is an arithmetic number, because the mean of its divisors is an integer number (12377155).

Almost surely, 2^91005109 is an apocalyptic number.

It is an amenable number.

91005109 is a deficient number, since it is larger than the sum of its proper divisors (8012131).

91005109 is a wasteful number, since it uses less digits than its factorization.

91005109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72279.

The product of its (nonzero) digits is 405, while the sum is 25.

The square root of 91005109 is about 9539.6597947726. The cubic root of 91005109 is about 449.8025619462.

The spelling of 91005109 in words is "ninety-one million, five thousand, one hundred nine".