2218636 has 48 divisors (see below), whose sum is σ = 4838400. Its totient is φ = 868608.

The previous prime is 2218621. The next prime is 2218663. The reversal of 2218636 is 6368122.

2218636 = T₁ + T₂ + ... + T₂₃₆.

2218636 is a nontrivial binomial coefficient, being equal to C(238, 3).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is the 236-th tetrahedral number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28045 + ... + 28123.

It is an arithmetic number, because the mean of its divisors is an integer number (100800).

2^2218636 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2218636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2419200).

2218636 is an abundant number, since it is smaller than the sum of its proper divisors (2619764).

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

2218636 is a wasteful number, since it uses less digits than its factorization.

2218636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 164 counting only the distinct ones).

The product of its digits is 3456, while the sum is 28.

The square root of 2218636 is about 1489.5086438151. The cubic root of 2218636 is about 130.4253523166.

It can be divided in two parts, 22186 and 36, that added together give a palindrome (22222).

The spelling of 2218636 in words is "two million, two hundred eighteen thousand, six hundred thirty-six".