2181226 has 4 divisors (see below), whose sum is σ = 3271842. Its totient is φ = 1090612.

The previous prime is 2181217. The next prime is 2181227. The reversal of 2181226 is 6221812.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1565001 + 616225 = 1251^2 + 785^2 .

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.

It is a junction number, because it is equal to n+sod(n) for n = 2181197 and 2181206.

It is not an unprimeable number, because it can be changed into a prime (2181227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545305 + ... + 545308.

2^2181226 is an apocalyptic number.

2181226 is a deficient number, since it is larger than the sum of its proper divisors (1090616).

2181226 is a wasteful number, since it uses less digits than its factorization.

2181226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1090615.

The product of its digits is 384, while the sum is 22.

The square root of 2181226 is about 1476.8974236554. The cubic root of 2181226 is about 129.6881281530.

It can be divided in two parts, 218 and 1226, that added together give a square (1444 = 38²).

The spelling of 2181226 in words is "two million, one hundred eighty-one thousand, two hundred twenty-six".