161810111 has 8 divisors (see below), whose sum is σ = 172790400. Its totient is φ = 151189920.

The previous prime is 161810081. The next prime is 161810119. The reversal of 161810111 is 111018161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161810111 - 2¹⁴ = 161793727 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 (161810119) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89096 + ... + 90893.

It is an arithmetic number, because the mean of its divisors is an integer number (21598800).

Almost surely, 2^161810111 is an apocalyptic number.

161810111 is a deficient number, since it is larger than the sum of its proper divisors (10980289).

161810111 is a wasteful number, since it uses less digits than its factorization.

161810111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180049.

The product of its (nonzero) digits is 48, while the sum is 20.

The square root of 161810111 is about 12720.4603297208. The cubic root of 161810111 is about 544.9230999991.

Adding to 161810111 its reverse (111018161), we get a palindrome (272828272).

The spelling of 161810111 in words is "one hundred sixty-one million, eight hundred ten thousand, one hundred eleven".