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12880 = 245723
BaseRepresentation
bin11001001010000
3122200001
43021100
5403010
6135344
752360
oct31120
918601
1012880
11974a
127554
135b2a
1449a0
153c3a
hex3250

12880 has 40 divisors (see below), whose sum is σ = 35712. Its totient is φ = 4224.

The previous prime is 12853. The next prime is 12889. The reversal of 12880 is 8821.

12880 = T13 + T14 + ... + T42.

It is a happy number.

12880 is a nontrivial binomial coefficient, being equal to C(161, 2).

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (19) coincides with the sum of the digits of its distinct prime factors.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12889) by changing a digit.

12880 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 (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 549 + ... + 571.

212880 is an apocalyptic number.

12880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12880 is the 160-th triangular number.

12880 is the 54-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17856).

12880 is an abundant number, since it is smaller than the sum of its proper divisors (22832).

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

12880 is a wasteful number, since it uses less digits than its factorization.

12880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43 (or 37 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 12880 is about 113.4900876729. The cubic root of 12880 is about 23.4407743573.

The spelling of 12880 in words is "twelve thousand, eight hundred eighty".