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7280 = 245713

7280 has 40 divisors (see below), whose sum is σ = 20832. Its totient is φ = 2304.

The previous prime is 7253. The next prime is 7283. The reversal of 7280 is 827.

7280 = T25 + T26 + ... + T38.

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

It is an Ulam number.

It is a plaindrome in base 15.

It is a zygodrome in base 2 and base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7283) by changing a digit.

7280 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 554 + ... + 566.

27280 is an apocalyptic number.

7280 is a gapful number since it is divisible by the number (70) 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 7280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10416).

7280 is an abundant number, since it is smaller than the sum of its proper divisors (13552).

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

7280 is a wasteful number, since it uses less digits than its factorization.

7280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 7280 is about 85.3229160308. The cubic root of 7280 is about 19.3810421669.

The spelling of 7280 in words is "seven thousand, two hundred eighty".