91493659778 has 8 divisors (see below), whose sum is σ = 137373606720. Its totient is φ = 45702457540.

The previous prime is 91493659759. The next prime is 91493659781. The reversal of 91493659778 is 87795639419.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22183598 + ... + 22187721.

It is an arithmetic number, because the mean of its divisors is an integer number (17171700840).

Almost surely, 2^91493659778 is an apocalyptic number.

91493659778 is a deficient number, since it is larger than the sum of its proper divisors (45879946942).

91493659778 is a wasteful number, since it uses less digits than its factorization.

91493659778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44372352.

The product of its digits is 102876480, while the sum is 68.

The spelling of 91493659778 in words is "ninety-one billion, four hundred ninety-three million, six hundred fifty-nine thousand, seven hundred seventy-eight".