228077221 has 4 divisors (see below), whose sum is σ = 228592512. Its totient is φ = 227561932.

The previous prime is 228077209. The next prime is 228077233. The reversal of 228077221 is 122770822.

228077221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122770822 = 2 ⋅61385411.

It is an interprime number because it is at equal distance from previous prime (228077209) and next prime (228077233).

It is a cyclic number.

It is not a de Polignac number, because 228077221 - 2¹¹ = 228075173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228077251) 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, 256981 + ... + 257866.

It is an arithmetic number, because the mean of its divisors is an integer number (57148128).

Almost surely, 2^228077221 is an apocalyptic number.

It is an amenable number.

228077221 is a deficient number, since it is larger than the sum of its proper divisors (515291).

228077221 is an equidigital number, since it uses as much as digits as its factorization.

228077221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515290.

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 228077221 is about 15102.2256968965. The cubic root of 228077221 is about 610.9804362273.

The spelling of 228077221 in words is "two hundred twenty-eight million, seventy-seven thousand, two hundred twenty-one".