161723911 has 2 divisors, whose sum is σ = 161723912. Its totient is φ = 161723910.

The previous prime is 161723843. The next prime is 161723921. The reversal of 161723911 is 119327161.

161723911 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161723911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161723921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80861955 + 80861956.

It is an arithmetic number, because the mean of its divisors is an integer number (80861956).

Almost surely, 2^161723911 is an apocalyptic number.

161723911 is a deficient number, since it is larger than the sum of its proper divisors (1).

161723911 is an equidigital number, since it uses as much as digits as its factorization.

161723911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2268, while the sum is 31.

The square root of 161723911 is about 12717.0716361905. The cubic root of 161723911 is about 544.8263184187.

The spelling of 161723911 in words is "one hundred sixty-one million, seven hundred twenty-three thousand, nine hundred eleven".