228521000 has 32 divisors (see below), whose sum is σ = 534741480. Its totient is φ = 91408000.

The previous prime is 228520997. The next prime is 228521017. The reversal of 228521000 is 125822.

It can be written as a sum of positive squares in 4 ways, for example, as 99880036 + 128640964 = 9994^2 + 11342^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113261 + ... + 115260.

Almost surely, 2^228521000 is an apocalyptic number.

228521000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

228521000 is an abundant number, since it is smaller than the sum of its proper divisors (306220480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

228521000 is a wasteful number, since it uses less digits than its factorization.

228521000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228542 (or 228528 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 228521000 is about 15116.9110601339. The cubic root of 228521000 is about 611.3764492085.

Adding to 228521000 its reverse (125822), we get a palindrome (228646822).

The spelling of 228521000 in words is "two hundred twenty-eight million, five hundred twenty-one thousand".