2191066 has 16 divisors (see below), whose sum is σ = 3495240. Its totient is φ = 1028160.

The previous prime is 2191051. The next prime is 2191067. The reversal of 2191066 is 6601912.

It can be written as a sum of positive squares in 4 ways, for example, as 2163841 + 27225 = 1471^2 + 165^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 2191066.

It is not an unprimeable number, because it can be changed into a prime (2191067) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1636 + ... + 2656.

2^2191066 is an apocalyptic number.

2191066 is a deficient number, since it is larger than the sum of its proper divisors (1304174).

2191066 is a wasteful number, since it uses less digits than its factorization.

2191066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1089.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 2191066 is about 1480.2249828996. The cubic root of 2191066 is about 129.8828530469.

Adding to 2191066 its reverse (6601912), we get a palindrome (8792978).

The spelling of 2191066 in words is "two million, one hundred ninety-one thousand, sixty-six".