221840204 has 6 divisors (see below), whose sum is σ = 388220364. Its totient is φ = 110920100.

The previous prime is 221840161. The next prime is 221840207. The reversal of 221840204 is 402048122.

It is a happy number.

It is a super-2 number, since 2×221840204² = 98426152221523232, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221840204.

It is not an unprimeable number, because it can be changed into a prime (221840207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27730022 + ... + 27730029.

It is an arithmetic number, because the mean of its divisors is an integer number (64703394).

Almost surely, 2^221840204 is an apocalyptic number.

It is an amenable number.

221840204 is a deficient number, since it is larger than the sum of its proper divisors (166380160).

221840204 is a wasteful number, since it uses less digits than its factorization.

221840204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55460055 (or 55460053 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 23.

The square root of 221840204 is about 14894.3010577872. The cubic root of 221840204 is about 605.3595786079.

Adding to 221840204 its reverse (402048122), we get a palindrome (623888326).

The spelling of 221840204 in words is "two hundred twenty-one million, eight hundred forty thousand, two hundred four".