91297609 has 4 divisors (see below), whose sum is σ = 98320516. Its totient is φ = 84274704.

The previous prime is 91297607. The next prime is 91297621. The reversal of 91297609 is 90679219.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30769209 + 60528400 = 5547^2 + 7780^2 .

It is a cyclic number.

It is not a de Polignac number, because 91297609 - 2¹ = 91297607 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91297601) 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 3 ways as a sum of consecutive naturals, for example, 3511434 + ... + 3511459.

It is an arithmetic number, because the mean of its divisors is an integer number (24580129).

Almost surely, 2^91297609 is an apocalyptic number.

It is an amenable number.

91297609 is a deficient number, since it is larger than the sum of its proper divisors (7022907).

91297609 is a wasteful number, since it uses less digits than its factorization.

91297609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7022906.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 91297609 is about 9554.9782312677. The cubic root of 91297609 is about 450.2839508300.

The spelling of 91297609 in words is "ninety-one million, two hundred ninety-seven thousand, six hundred nine".