166220105 has 4 divisors (see below), whose sum is σ = 199464132. Its totient is φ = 132976080.

The previous prime is 166220077. The next prime is 166220107. The reversal of 166220105 is 501022661.

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 39702601 + 126517504 = 6301^2 + 11248^2 .

It is not a de Polignac number, because 166220105 - 2⁸ = 166219849 is a prime.

It is a super-2 number, since 2×166220105² = 55258246612422050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166220107) 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, 16622006 + ... + 16622015.

It is an arithmetic number, because the mean of its divisors is an integer number (49866033).

Almost surely, 2^166220105 is an apocalyptic number.

It is an amenable number.

166220105 is a deficient number, since it is larger than the sum of its proper divisors (33244027).

166220105 is an equidigital number, since it uses as much as digits as its factorization.

166220105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33244026.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 166220105 is about 12892.6376277316. The cubic root of 166220105 is about 549.8292638084.

Adding to 166220105 its reverse (501022661), we get a palindrome (667242766).

The spelling of 166220105 in words is "one hundred sixty-six million, two hundred twenty thousand, one hundred five".