• 240 can be written using four 4's:

See also 113.

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240 has 20 divisors (see below), whose sum is σ = 744. Its totient is φ = 64.

The previous prime is 239. The next prime is 241. The reversal of 240 is 42.

It is a Jordan-Polya number, since it can be written as 5! ⋅ 2!.

240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (239) and next prime (241).

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

240 is an idoneal number.

It is a plaindrome in base 13.

It is a nialpdrome in base 2, base 3, base 4, base 15 and base 16.

It is a zygodrome in base 2 and base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (241) by changing a digit.

In principle, a polygon with 240 sides can be constructed with ruler and compass.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46 + ... + 50.

240 is a highly composite number, because it has more divisors than any smaller number.

240 is a superabundant number, because it has a larger abundancy index than any smaller number.

240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

240 is a droll number since its even prime factors and its odd prime factors have the same sum.

It is a pronic number, being equal to 15×16.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (372).

240 is an abundant number, since it is smaller than the sum of its proper divisors (504).

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

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

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

The sum of its prime factors is 16 (or 10 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 6.

The square root of 240 is about 15.4919333848. The cubic root of 240 is about 6.2144650119.

Adding to 240 its reverse (42), we get a palindrome (282).

The spelling of 240 in words is "two hundred forty", and thus it is an aban number and an iban number.