228305 has 16 divisors (see below), whose sum is σ = 342144. Its totient is φ = 142080.

The previous prime is 228301. The next prime is 228307. The reversal of 228305 is 503822.

It is not a de Polignac number, because 228305 - 2² = 228301 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 (228301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89 + ... + 681.

It is an arithmetic number, because the mean of its divisors is an integer number (21384).

It is the magic constant of a 77 × 77 magic square.

2²²⁸³⁰⁵ is an apocalyptic number.

It is an amenable number.

228305 is a deficient number, since it is larger than the sum of its proper divisors (113839).

228305 is a wasteful number, since it uses less digits than its factorization.

228305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 616.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 228305 is about 477.8127248201. The cubic root of 228305 is about 61.1183762406.

It can be divided in two parts, 22 and 8305, that multiplied together give a triangular number (182710 = T₆₀₄).

The spelling of 228305 in words is "two hundred twenty-eight thousand, three hundred five".