28238240 has 24 divisors (see below), whose sum is σ = 66713220. Its totient is φ = 11295232.

The previous prime is 28238233. The next prime is 28238251. The reversal of 28238240 is 4283282.

It can be written as a sum of positive squares in 2 ways, for example, as 27164944 + 1073296 = 5212^2 + 1036^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88085 + ... + 88404.

Almost surely, 2^28238240 is an apocalyptic number.

28238240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28238240 is an abundant number, since it is smaller than the sum of its proper divisors (38474980).

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

28238240 is a wasteful number, since it uses less digits than its factorization.

28238240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176504 (or 176496 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 29.

The square root of 28238240 is about 5313.9665034699. The cubic root of 28238240 is about 304.5177005159.

The spelling of 28238240 in words is "twenty-eight million, two hundred thirty-eight thousand, two hundred forty".