2166705 has 24 divisors (see below), whose sum is σ = 3804840. Its totient is φ = 1140480.

The previous prime is 2166691. The next prime is 2166709. The reversal of 2166705 is 5076612.

It can be written as a sum of positive squares in 4 ways, for example, as 23409 + 2143296 = 153^2 + 1464^2 .

It is not a de Polignac number, because 2166705 - 2⁵ = 2166673 is a prime.

It is a super-2 number, since 2×2166705² = 9389221114050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2166709) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3735 + ... + 4275.

It is an arithmetic number, because the mean of its divisors is an integer number (158535).

2^2166705 is an apocalyptic number.

It is an amenable number.

2166705 is a deficient number, since it is larger than the sum of its proper divisors (1638135).

2166705 is a wasteful number, since it uses less digits than its factorization.

2166705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 641 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 2166705 is about 1471.9731655163. The cubic root of 2166705 is about 129.3996977284.

The spelling of 2166705 in words is "two million, one hundred sixty-six thousand, seven hundred five".