91809644690819 has 6 divisors (see below), whose sum is σ = 100914733420620. Its totient is φ = 83463313355180.

The previous prime is 91809644690779. The next prime is 91809644690833.

91809644690819 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 91809644690819 - 2³⁶ = 91740925214083 is a prime.

It is a super-2 number, since 2×91809644690819² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91809644690839) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 379378696949 + ... + 379378697190.

It is an arithmetic number, because the mean of its divisors is an integer number (16819122236770).

Almost surely, 2^{91809644690819} is an apocalyptic number.

91809644690819 is a deficient number, since it is larger than the sum of its proper divisors (9105088729801).

91809644690819 is a wasteful number, since it uses less digits than its factorization.

91809644690819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 758757394161 (or 758757394150 counting only the distinct ones).

The product of its (nonzero) digits is 241864704, while the sum is 74.

The spelling of 91809644690819 in words is "ninety-one trillion, eight hundred nine billion, six hundred forty-four million, six hundred ninety thousand, eight hundred nineteen".