220161 has 4 divisors (see below), whose sum is σ = 293552. Its totient is φ = 146772.

The previous prime is 220151. The next prime is 220163. The reversal of 220161 is 161022.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 220161 - 2⁹ = 219649 is a prime.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 220161.

It is not an unprimeable number, because it can be changed into a prime (220163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36691 + ... + 36696.

It is an arithmetic number, because the mean of its divisors is an integer number (73388).

It is a Proth number, since it is equal to 215 ⋅ 2¹⁰ + 1 and 215 < 2¹⁰.

2²²⁰¹⁶¹ is an apocalyptic number.

It is an amenable number.

220161 is a deficient number, since it is larger than the sum of its proper divisors (73391).

220161 is an equidigital number, since it uses as much as digits as its factorization.

220161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73390.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 220161 is about 469.2131711706. The cubic root of 220161 is about 60.3828299367.

Adding to 220161 its reverse (161022), we get a palindrome (381183).

The spelling of 220161 in words is "two hundred twenty thousand, one hundred sixty-one".