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87040 = 210517
BaseRepresentation
bin10101010000000000
311102101201
4111100000
510241130
61510544
7511522
oct252000
9142351
1087040
115a438
1242454
1330805
1423a12
151abca
hex15400

87040 has 44 divisors (see below), whose sum is σ = 221076. Its totient is φ = 32768.

The previous prime is 87037. The next prime is 87041. The reversal of 87040 is 4078.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 50176 + 36864 = 224^2 + 192^2 .

It is a nialpdrome in base 4.

It is a zygodrome in base 4.

It is a junction number, because it is equal to n+sod(n) for n = 86999 and 87017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87041) by changing a digit.

In principle, a polygon with 87040 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, 5112 + ... + 5128.

287040 is an apocalyptic number.

87040 is a gapful number since it is divisible by the number (80) 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 87040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110538).

87040 is an abundant number, since it is smaller than the sum of its proper divisors (134036).

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

87040 is a wasteful number, since it uses less digits than its factorization.

87040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42 (or 24 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 87040 is about 295.0254226334. The cubic root of 87040 is about 44.3172660540.

The spelling of 87040 in words is "eighty-seven thousand, forty".