28394280 has 128 divisors (see below), whose sum is σ = 96422400. Its totient is φ = 7430400.

The previous prime is 28394257. The next prime is 28394287. The reversal of 28394280 is 8249382.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (28394287) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 65665 + ... + 66095.

It is an arithmetic number, because the mean of its divisors is an integer number (753300).

Almost surely, 2^28394280 is an apocalyptic number.

28394280 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 28394280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48211200).

28394280 is an abundant number, since it is smaller than the sum of its proper divisors (68028120).

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

28394280 is a wasteful number, since it uses less digits than its factorization.

28394280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512 (or 502 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 28394280 is about 5328.6283413276. The cubic root of 28394280 is about 305.0775758955.

The spelling of 28394280 in words is "twenty-eight million, three hundred ninety-four thousand, two hundred eighty".