2201666 has 4 divisors (see below), whose sum is σ = 3302502. Its totient is φ = 1100832.

The previous prime is 2201627. The next prime is 2201669. The reversal of 2201666 is 6661022.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6661022 = 2 ⋅3330511.

It can be written as a sum of positive squares in only one way, i.e., 1243225 + 958441 = 1115^2 + 979^2 .

It is not an unprimeable number, because it can be changed into a prime (2201669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 550415 + ... + 550418.

2^2201666 is an apocalyptic number.

2201666 is a deficient number, since it is larger than the sum of its proper divisors (1100836).

2201666 is a wasteful number, since it uses less digits than its factorization.

2201666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100835.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 2201666 is about 1483.8011996221. The cubic root of 2201666 is about 130.0919664826.

Adding to 2201666 its reverse (6661022), we get a palindrome (8862688).

The spelling of 2201666 in words is "two million, two hundred one thousand, six hundred sixty-six".