221306804 has 12 divisors (see below), whose sum is σ = 387771300. Its totient is φ = 110515008.

The previous prime is 221306803. The next prime is 221306809. The reversal of 221306804 is 408603122.

It can be written as a sum of positive squares in 2 ways, for example, as 187690000 + 33616804 = 13700^2 + 5798^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221306803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30959 + ... + 37430.

It is an arithmetic number, because the mean of its divisors is an integer number (32314275).

Almost surely, 2^221306804 is an apocalyptic number.

It is an amenable number.

221306804 is a deficient number, since it is larger than the sum of its proper divisors (166464496).

221306804 is a wasteful number, since it uses less digits than its factorization.

221306804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69202 (or 69200 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 221306804 is about 14876.3841036725. The cubic root of 221306804 is about 604.8740069579.

Adding to 221306804 its reverse (408603122), we get a palindrome (629909926).

The spelling of 221306804 in words is "two hundred twenty-one million, three hundred six thousand, eight hundred four".