11891880017 has 2 divisors, whose sum is σ = 11891880018. Its totient is φ = 11891880016.

The previous prime is 11891879941. The next prime is 11891880019. The reversal of 11891880017 is 71008819811.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7271143441 + 4620736576 = 85271^2 + 67976^2 .

It is an emirp because it is prime and its reverse (71008819811) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11891880017 - 2¹⁰ = 11891878993 is a prime.

Together with 11891880019, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11891880017.

It is not a weakly prime, because it can be changed into another prime (11891880019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5945940008 + 5945940009.

It is an arithmetic number, because the mean of its divisors is an integer number (5945940009).

Almost surely, 2^11891880017 is an apocalyptic number.

It is an amenable number.

11891880017 is a deficient number, since it is larger than the sum of its proper divisors (1).

11891880017 is an equidigital number, since it uses as much as digits as its factorization.

11891880017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 44.

The spelling of 11891880017 in words is "eleven billion, eight hundred ninety-one million, eight hundred eighty thousand, seventeen".