2221812 has 18 divisors (see below), whose sum is σ = 5616338. Its totient is φ = 740592.

The previous prime is 2221789. The next prime is 2221829. The reversal of 2221812 is 2181222.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1454436 + 767376 = 1206^2 + 876^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 30823 + ... + 30894.

2^2221812 is an apocalyptic number.

It is an amenable number.

2221812 is an abundant number, since it is smaller than the sum of its proper divisors (3394526).

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

2221812 is a wasteful number, since it uses less digits than its factorization.

2221812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61727 (or 61722 counting only the distinct ones).

The product of its digits is 128, while the sum is 18.

The square root of 2221812 is about 1490.5743859332. The cubic root of 2221812 is about 130.4875577163.

The spelling of 2221812 in words is "two million, two hundred twenty-one thousand, eight hundred twelve".