191709796889 has 4 divisors (see below), whose sum is σ = 206456704356. Its totient is φ = 176962889424.

The previous prime is 191709796813. The next prime is 191709796897. The reversal of 191709796889 is 988697907191.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 988697907191 = 17 ⋅58158700423.

It can be written as a sum of positive squares in 2 ways, for example, as 13400377600 + 178309419289 = 115760^2 + 422267^2 .

It is a cyclic number.

It is not a de Polignac number, because 191709796889 - 2¹² = 191709792793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191709796189) 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, 7373453714 + ... + 7373453739.

It is an arithmetic number, because the mean of its divisors is an integer number (51614176089).

Almost surely, 2^191709796889 is an apocalyptic number.

It is an amenable number.

191709796889 is a deficient number, since it is larger than the sum of its proper divisors (14746907467).

191709796889 is a wasteful number, since it uses less digits than its factorization.

191709796889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14746907466.

The product of its (nonzero) digits is 123451776, while the sum is 74.

The spelling of 191709796889 in words is "one hundred ninety-one billion, seven hundred nine million, seven hundred ninety-six thousand, eight hundred eighty-nine".