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BaseRepresentation
bin101011111000
310212000
4223320
542213
621000
711121
oct5370
93760
102808
112123
121760
131380
141048
15c73
hexaf8

2808 has 32 divisors (see below), whose sum is σ = 8400. Its totient is φ = 864.

The previous prime is 2803. The next prime is 2819. The reversal of 2808 is 8082.

It is a Cunningham number, because it is equal to 532-1.

2808 is an esthetic number in base 11, because in such base its adjacent digits differ by 1.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 6 and base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2801) by changing a digit.

2808 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 210 + ... + 222.

22808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4200).

2808 is an abundant number, since it is smaller than the sum of its proper divisors (5592).

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

2808 is a wasteful number, since it uses less digits than its factorization.

2808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28 (or 18 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 2808 is about 52.9905651980. The cubic root of 2808 is about 14.1080081263.

The spelling of 2808 in words is "two thousand, eight hundred eight".