91765587449 has 4 divisors (see below), whose sum is σ = 91766299236. Its totient is φ = 91764875664.

The previous prime is 91765587437. The next prime is 91765587451. The reversal of 91765587449 is 94478556719.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 2256915049 + 89508672400 = 47507^2 + 299180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91765587449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91765587479) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102254 + ... + 440439.

It is an arithmetic number, because the mean of its divisors is an integer number (22941574809).

Almost surely, 2^91765587449 is an apocalyptic number.

It is an amenable number.

91765587449 is a deficient number, since it is larger than the sum of its proper divisors (711787).

91765587449 is a wasteful number, since it uses less digits than its factorization.

91765587449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 711786.

The product of its digits is 76204800, while the sum is 65.

The spelling of 91765587449 in words is "ninety-one billion, seven hundred sixty-five million, five hundred eighty-seven thousand, four hundred forty-nine".