28164240 has 320 divisors, whose sum is σ = 112492800. Its totient is φ = 6414336.

The previous prime is 28164239. The next prime is 28164247. The reversal of 28164240 is 4246182.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (28164247) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 477331 + ... + 477389.

It is an arithmetic number, because the mean of its divisors is an integer number (351540).

Almost surely, 2^28164240 is an apocalyptic number.

28164240 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 28164240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56246400).

28164240 is an abundant number, since it is smaller than the sum of its proper divisors (84328560).

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

28164240 is a wasteful number, since it uses less digits than its factorization.

28164240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 28164240 is about 5306.9991520632. Note that the first 3 decimals coincide. The cubic root of 28164240 is about 304.2514655249.

It can be divided in two parts, 2816 and 4240, that added together give a square (7056 = 84²).

The spelling of 28164240 in words is "twenty-eight million, one hundred sixty-four thousand, two hundred forty".