161873111 has 4 divisors (see below), whose sum is σ = 163692000. Its totient is φ = 160054224.

The previous prime is 161873087. The next prime is 161873147. The reversal of 161873111 is 111378161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 111378161 = 419 ⋅265819.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161873111 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 (161873191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 909311 + ... + 909488.

It is an arithmetic number, because the mean of its divisors is an integer number (40923000).

Almost surely, 2^161873111 is an apocalyptic number.

161873111 is a deficient number, since it is larger than the sum of its proper divisors (1818889).

161873111 is an equidigital number, since it uses as much as digits as its factorization.

161873111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1818888.

The product of its digits is 1008, while the sum is 29.

The square root of 161873111 is about 12722.9364142088. The cubic root of 161873111 is about 544.9938118984.

The spelling of 161873111 in words is "one hundred sixty-one million, eight hundred seventy-three thousand, one hundred eleven".