221204144 has 20 divisors (see below), whose sum is σ = 489809424. Its totient is φ = 94801728.

The previous prime is 221204129. The next prime is 221204161. The reversal of 221204144 is 441402122.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 987407 + ... + 987630.

Almost surely, 2^221204144 is an apocalyptic number.

It is an amenable number.

221204144 is an abundant number, since it is smaller than the sum of its proper divisors (268605280).

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

221204144 is a wasteful number, since it uses less digits than its factorization.

221204144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1975052 (or 1975046 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 221204144 is about 14872.9332681889. The cubic root of 221204144 is about 604.7804626584.

Adding to 221204144 its reverse (441402122), we get a palindrome (662606266).

The spelling of 221204144 in words is "two hundred twenty-one million, two hundred four thousand, one hundred forty-four".