2191866 has 16 divisors (see below), whose sum is σ = 4399488. Its totient is φ = 728000.

The previous prime is 2191823. The next prime is 2191873. The reversal of 2191866 is 6681912.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1951 + ... + 2861.

It is an arithmetic number, because the mean of its divisors is an integer number (274968).

2^2191866 is an apocalyptic number.

2191866 is an abundant number, since it is smaller than the sum of its proper divisors (2207622).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2191866 is a wasteful number, since it uses less digits than its factorization.

2191866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1317.

The product of its digits is 5184, while the sum is 33.

The square root of 2191866 is about 1480.4951874289. The cubic root of 2191866 is about 129.8986586926.

The spelling of 2191866 in words is "two million, one hundred ninety-one thousand, eight hundred sixty-six".