161289911 has 2 divisors, whose sum is σ = 161289912. Its totient is φ = 161289910.

The previous prime is 161289899. The next prime is 161289913. The reversal of 161289911 is 119982161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161289911 - 2¹⁰ = 161288887 is a prime.

Together with 161289913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161289913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80644955 + 80644956.

It is an arithmetic number, because the mean of its divisors is an integer number (80644956).

Almost surely, 2^161289911 is an apocalyptic number.

161289911 is a deficient number, since it is larger than the sum of its proper divisors (1).

161289911 is an equidigital number, since it uses as much as digits as its factorization.

161289911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 38.

The square root of 161289911 is about 12699.9964960625. The cubic root of 161289911 is about 544.3385190738.

The spelling of 161289911 in words is "one hundred sixty-one million, two hundred eighty-nine thousand, nine hundred eleven".