28228280 has 32 divisors (see below), whose sum is σ = 64324800. Its totient is φ = 11147136.

The previous prime is 28228271. The next prime is 28228289. The reversal of 28228280 is 8282282.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28228271) and next prime (28228289).

It is a super-3 number, since 3×28228280³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28228289) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1307 + ... + 7626.

It is an arithmetic number, because the mean of its divisors is an integer number (2010150).

Almost surely, 2^28228280 is an apocalyptic number.

28228280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28228280 is an abundant number, since it is smaller than the sum of its proper divisors (36096520).

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

28228280 is a wasteful number, since it uses less digits than its factorization.

28228280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9023 (or 9019 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 32.

The square root of 28228280 is about 5313.0292677530. The cubic root of 28228280 is about 304.4818938349.

It can be divided in two parts, 282282 and 80, that multiplied together give a triangular number (22582560 = T₆₇₂₀).

The spelling of 28228280 in words is "twenty-eight million, two hundred twenty-eight thousand, two hundred eighty".