28233220 has 24 divisors (see below), whose sum is σ = 60893784. Its totient is φ = 10987776.

The previous prime is 28233217. The next prime is 28233223. The reversal of 28233220 is 2233282.

It is an interprime number because it is at equal distance from previous prime (28233217) and next prime (28233223).

It can be written as a sum of positive squares in 4 ways, for example, as 10810944 + 17422276 = 3288^2 + 4174^2 .

It is a super-2 number, since 2×28233220² = 1594229423136800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28233191 and 28233200.

It is not an unprimeable number, because it can be changed into a prime (28233223) 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, 18337 + ... + 19816.

It is an arithmetic number, because the mean of its divisors is an integer number (2537241).

Almost surely, 2^28233220 is an apocalyptic number.

28233220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28233220 is an abundant number, since it is smaller than the sum of its proper divisors (32660564).

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

28233220 is a wasteful number, since it uses less digits than its factorization.

28233220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38199 (or 38197 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 28233220 is about 5313.4941422759. The cubic root of 28233220 is about 304.4996544261.

The spelling of 28233220 in words is "twenty-eight million, two hundred thirty-three thousand, two hundred twenty".