161318311 has 16 divisors (see below), whose sum is σ = 203125248. Its totient is φ = 124452000.

The previous prime is 161318293. The next prime is 161318317. The reversal of 161318311 is 113813161.

It is a cyclic number.

It is not a de Polignac number, because 161318311 - 2⁵ = 161318279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161318317) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2595 + ... + 18148.

It is an arithmetic number, because the mean of its divisors is an integer number (12695328).

Almost surely, 2^161318311 is an apocalyptic number.

161318311 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

161318311 is a deficient number, since it is larger than the sum of its proper divisors (41806937).

161318311 is a wasteful number, since it uses less digits than its factorization.

161318311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20862.

The product of its digits is 432, while the sum is 25.

The square root of 161318311 is about 12701.1145573922. The cubic root of 161318311 is about 544.3704663225.

It can be divided in two parts, 16131 and 8311, that added together give a palindrome (24442).

The spelling of 161318311 in words is "one hundred sixty-one million, three hundred eighteen thousand, three hundred eleven".