2166645 has 32 divisors (see below), whose sum is σ = 3838464. Its totient is φ = 1036800.

The previous prime is 2166629. The next prime is 2166673. The reversal of 2166645 is 5466612.

2166645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2166645 - 2⁴ = 2166629 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7860 + ... + 8130.

It is an arithmetic number, because the mean of its divisors is an integer number (119952).

2^2166645 is an apocalyptic number.

It is an amenable number.

2166645 is a deficient number, since it is larger than the sum of its proper divisors (1671819).

2166645 is a wasteful number, since it uses less digits than its factorization.

2166645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333.

The product of its digits is 8640, while the sum is 30.

The square root of 2166645 is about 1471.9527845689. The cubic root of 2166645 is about 129.3985032797.

It can be divided in two parts, 21 and 66645, that added together give a palindrome (66666).

The spelling of 2166645 in words is "two million, one hundred sixty-six thousand, six hundred forty-five".