161611105 has 4 divisors (see below), whose sum is σ = 193933332. Its totient is φ = 129288880.

The previous prime is 161611103. The next prime is 161611111. The reversal of 161611105 is 501116161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 100020001 + 61591104 = 10001^2 + 7848^2 .

It is not a de Polignac number, because 161611105 - 2¹ = 161611103 is a prime.

It is a super-2 number, since 2×161611105² = 52236298518642050, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161611103) 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, 16161106 + ... + 16161115.

It is an arithmetic number, because the mean of its divisors is an integer number (48483333).

Almost surely, 2^161611105 is an apocalyptic number.

It is an amenable number.

161611105 is a deficient number, since it is larger than the sum of its proper divisors (32322227).

161611105 is an equidigital number, since it uses as much as digits as its factorization.

161611105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32322226.

The product of its (nonzero) digits is 180, while the sum is 22.

The square root of 161611105 is about 12712.6356433275. The cubic root of 161611105 is about 544.6996128239.

Adding to 161611105 its reverse (501116161), we get a palindrome (662727266).

It can be divided in two parts, 1616 and 11105, that added together give a palindrome (12721).

The spelling of 161611105 in words is "one hundred sixty-one million, six hundred eleven thousand, one hundred five".