228316221 has 24 divisors (see below), whose sum is σ = 379177344. Its totient is φ = 129679200.

The previous prime is 228316211. The next prime is 228316223. The reversal of 228316221 is 122613822.

228316221 is a `hidden beast` number, since 2 + 2 + 8 + 31 + 622 + 1 = 666.

It is not a de Polignac number, because 228316221 - 2⁷ = 228316093 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228316223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 330 + ... + 21371.

It is an arithmetic number, because the mean of its divisors is an integer number (15799056).

Almost surely, 2^228316221 is an apocalyptic number.

228316221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

228316221 is a deficient number, since it is larger than the sum of its proper divisors (150861123).

228316221 is a wasteful number, since it uses less digits than its factorization.

228316221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21881 (or 21878 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 228316221 is about 15110.1363660293. The cubic root of 228316221 is about 611.1937752994.

The spelling of 228316221 in words is "two hundred twenty-eight million, three hundred sixteen thousand, two hundred twenty-one".