221404233 has 16 divisors (see below), whose sum is σ = 308745216. Its totient is φ = 140862480.

The previous prime is 221404231. The next prime is 221404237. The reversal of 221404233 is 332404122.

It is not a de Polignac number, because 221404233 - 2¹ = 221404231 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221404231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28788 + ... + 35658.

It is an arithmetic number, because the mean of its divisors is an integer number (19296576).

Almost surely, 2^221404233 is an apocalyptic number.

221404233 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

221404233 is a deficient number, since it is larger than the sum of its proper divisors (87340983).

221404233 is a wasteful number, since it uses less digits than its factorization.

221404233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7364.

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 221404233 is about 14879.6583630136. The cubic root of 221404233 is about 604.9627579926.

Adding to 221404233 its reverse (332404122), we get a palindrome (553808355).

The spelling of 221404233 in words is "two hundred twenty-one million, four hundred four thousand, two hundred thirty-three".