1665166 has 4 divisors (see below), whose sum is σ = 2497752. Its totient is φ = 832582.

The previous prime is 1665161. The next prime is 1665173. The reversal of 1665166 is 6615661.

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

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 416290 + ... + 416293.

It is an arithmetic number, because the mean of its divisors is an integer number (624438).

2^1665166 is an apocalyptic number.

1665166 is a deficient number, since it is larger than the sum of its proper divisors (832586).

1665166 is an equidigital number, since it uses as much as digits as its factorization.

1665166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832585.

The product of its digits is 6480, while the sum is 31.

The square root of 1665166 is about 1290.4131121466. The cubic root of 1665166 is about 118.5275147227.

The spelling of 1665166 in words is "one million, six hundred sixty-five thousand, one hundred sixty-six".