91779058799 has 4 divisors (see below), whose sum is σ = 94943853960. Its totient is φ = 88614263640.

The previous prime is 91779058793. The next prime is 91779058837. The reversal of 91779058799 is 99785097719.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99785097719 = 83 ⋅1202230093.

It is a cyclic number.

It is not a de Polignac number, because 91779058799 - 2²⁰ = 91778010223 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 (91779058793) 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, 1582397537 + ... + 1582397594.

It is an arithmetic number, because the mean of its divisors is an integer number (23735963490).

Almost surely, 2^91779058799 is an apocalyptic number.

91779058799 is a deficient number, since it is larger than the sum of its proper divisors (3164795161).

91779058799 is a wasteful number, since it uses less digits than its factorization.

91779058799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3164795160.

The product of its (nonzero) digits is 90016920, while the sum is 71.

The spelling of 91779058799 in words is "ninety-one billion, seven hundred seventy-nine million, fifty-eight thousand, seven hundred ninety-nine".