91768109 has 4 divisors (see below), whose sum is σ = 92280960. Its totient is φ = 91255260.

The previous prime is 91768099. The next prime is 91768129. The reversal of 91768109 is 90186719.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91768109 - 2²⁰ = 90719533 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 (91768129) 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, 256157 + ... + 256514.

It is an arithmetic number, because the mean of its divisors is an integer number (23070240).

Almost surely, 2^91768109 is an apocalyptic number.

It is an amenable number.

91768109 is a deficient number, since it is larger than the sum of its proper divisors (512851).

91768109 is a wasteful number, since it uses less digits than its factorization.

91768109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512850.

The product of its (nonzero) digits is 27216, while the sum is 41.

The square root of 91768109 is about 9579.5672658007. The cubic root of 91768109 is about 451.0561349851.

The spelling of 91768109 in words is "ninety-one million, seven hundred sixty-eight thousand, one hundred nine".