161666105 has 8 divisors (see below), whose sum is σ = 194462664. Its totient is φ = 129024000.

The previous prime is 161666083. The next prime is 161666137. The reversal of 161666105 is 501666161.

It can be written as a sum of positive squares in 4 ways, for example, as 11162281 + 150503824 = 3341^2 + 12268^2 .

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

It is not a de Polignac number, because 161666105 - 2¹⁸ = 161403961 is a prime.

It is a super-2 number, since 2×161666105² = 52271859011742050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36296 + ... + 40505.

It is an arithmetic number, because the mean of its divisors is an integer number (24307833).

Almost surely, 2^161666105 is an apocalyptic number.

It is an amenable number.

161666105 is a deficient number, since it is larger than the sum of its proper divisors (32796559).

161666105 is an equidigital number, since it uses as much as digits as its factorization.

161666105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77227.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 161666105 is about 12714.7986614024. The cubic root of 161666105 is about 544.7613971112.

The spelling of 161666105 in words is "one hundred sixty-one million, six hundred sixty-six thousand, one hundred five".