28660320 has 144 divisors (see below), whose sum is σ = 105395472. Its totient is φ = 7050240.

The previous prime is 28660279. The next prime is 28660321. The reversal of 28660320 is 2306682.

28660320 is a `hidden beast` number, since 286 + 60 + 320 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-3 number, since 3×28660320³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28660321) 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, 17955 + ... + 19485.

It is an arithmetic number, because the mean of its divisors is an integer number (731913).

Almost surely, 2^28660320 is an apocalyptic number.

28660320 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 28660320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52697736).

28660320 is an abundant number, since it is smaller than the sum of its proper divisors (76735152).

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

28660320 is a wasteful number, since it uses less digits than its factorization.

28660320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1565 (or 1554 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 28660320 is about 5353.5334126164. The cubic root of 28660320 is about 306.0274228916.

It can be divided in two parts, 286 and 60320, that added together give a palindrome (60606).

The spelling of 28660320 in words is "twenty-eight million, six hundred sixty thousand, three hundred twenty".