2165666 has 8 divisors (see below), whose sum is σ = 3317760. Its totient is φ = 1059748.

The previous prime is 2165663. The next prime is 2165671. The reversal of 2165666 is 6665612.

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

It is not an unprimeable number, because it can be changed into a prime (2165663) 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, 11426 + ... + 11613.

It is an arithmetic number, because the mean of its divisors is an integer number (414720).

2^2165666 is an apocalyptic number.

2165666 is a deficient number, since it is larger than the sum of its proper divisors (1152094).

2165666 is a wasteful number, since it uses less digits than its factorization.

2165666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23088.

The product of its digits is 12960, while the sum is 32.

The square root of 2165666 is about 1471.6201955668. The cubic root of 2165666 is about 129.3790107433.

The spelling of 2165666 in words is "two million, one hundred sixty-five thousand, six hundred sixty-six".