28268240 has 160 divisors (see below), whose sum is σ = 88494336. Its totient is φ = 8110080.

The previous prime is 28268237. The next prime is 28268267. The reversal of 28268240 is 4286282.

28268240 = 88² + 89² + ... + 440².

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 28268197 and 28268206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 79904 + ... + 80256.

Almost surely, 2^28268240 is an apocalyptic number.

28268240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28268240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44247168).

28268240 is an abundant number, since it is smaller than the sum of its proper divisors (60226096).

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

28268240 is a wasteful number, since it uses less digits than its factorization.

28268240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397 (or 391 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 32.

The square root of 28268240 is about 5316.7885043511. The cubic root of 28268240 is about 304.6255011173.

The spelling of 28268240 in words is "twenty-eight million, two hundred sixty-eight thousand, two hundred forty".