2201818 has 4 divisors (see below), whose sum is σ = 3302730. Its totient is φ = 1100908.

The previous prime is 2201807. The next prime is 2201827. The reversal of 2201818 is 8181022.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8181022 = 2 ⋅4090511.

It can be written as a sum of positive squares in only one way, i.e., 2152089 + 49729 = 1467^2 + 223^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

2201818 is a modest number, since divided by 1818 gives 220 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 550453 + ... + 550456.

2^2201818 is an apocalyptic number.

2201818 is a deficient number, since it is larger than the sum of its proper divisors (1100912).

2201818 is a wasteful number, since it uses less digits than its factorization.

2201818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100911.

The product of its (nonzero) digits is 256, while the sum is 22.

The square root of 2201818 is about 1483.8524185376. The cubic root of 2201818 is about 130.0949602040.

The spelling of 2201818 in words is "two million, two hundred one thousand, eight hundred eighteen".