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71280 = 2434511
BaseRepresentation
bin10001011001110000
310121210000
4101121300
54240110
61310000
7414546
oct213160
9117700
1071280
1149610
1235300
13265a1
141bd96
15161c0
hex11670

71280 has 100 divisors (see below), whose sum is σ = 270072. Its totient is φ = 17280.

The previous prime is 71263. The next prime is 71287. The reversal of 71280 is 8217.

Adding to 71280 its reverse (8217), we get a palindrome (79497).

It can be divided in two parts, 71 and 280, that added together give a triangular number (351 = T26).

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

It is a zygodrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71287) by changing a digit.

71280 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 19 ways as a sum of consecutive naturals, for example, 6475 + ... + 6485.

271280 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 71280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135036).

71280 is an abundant number, since it is smaller than the sum of its proper divisors (198792).

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

71280 is a wasteful number, since it uses less digits than its factorization.

71280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 71280 is about 266.9831455354. The cubic root of 71280 is about 41.4625393801.

The spelling of 71280 in words is "seventy-one thousand, two hundred eighty".