28517280 has 144 divisors (see below), whose sum is σ = 98939232. Its totient is φ = 6899200.

The previous prime is 28517273. The next prime is 28517287. The reversal of 28517280 is 8271582.

It is an interprime number because it is at equal distance from previous prime (28517273) and next prime (28517287).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (28517287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57835 + ... + 58325.

It is an arithmetic number, because the mean of its divisors is an integer number (687078).

Almost surely, 2^28517280 is an apocalyptic number.

28517280 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 28517280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49469616).

28517280 is an abundant number, since it is smaller than the sum of its proper divisors (70421952).

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

28517280 is a wasteful number, since it uses less digits than its factorization.

28517280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531 (or 512 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 33.

The square root of 28517280 is about 5340.1573010540. The cubic root of 28517280 is about 305.5174589540.

The spelling of 28517280 in words is "twenty-eight million, five hundred seventeen thousand, two hundred eighty".