1161118891 has 2 divisors, whose sum is σ = 1161118892. Its totient is φ = 1161118890.

The previous prime is 1161118883. The next prime is 1161118909. The reversal of 1161118891 is 1988111611.

It is a weak prime.

It is an emirp because it is prime and its reverse (1988111611) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1688111911 and 1191118861.

It is a cyclic number.

It is not a de Polignac number, because 1161118891 - 2³ = 1161118883 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1161118891.

It is not a weakly prime, because it can be changed into another prime (1161118991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580559445 + 580559446.

It is an arithmetic number, because the mean of its divisors is an integer number (580559446).

Almost surely, 2^1161118891 is an apocalyptic number.

1161118891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1161118891 is an equidigital number, since it uses as much as digits as its factorization.

1161118891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 37.

The square root of 1161118891 is about 34075.1946582848. The cubic root of 1161118891 is about 1051.0552930757.

The spelling of 1161118891 in words is "one billion, one hundred sixty-one million, one hundred eighteen thousand, eight hundred ninety-one".