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80640 = 283257
BaseRepresentation
bin10011101100000000
311002121200
4103230000
510040030
61421200
7454050
oct235400
9132550
1080640
115564a
123a800
132a921
1421560
1518d60
hex13b00

80640 has 108 divisors (see below), whose sum is σ = 318864. Its totient is φ = 18432.

The previous prime is 80629. The next prime is 80651. The reversal of 80640 is 4608.

It is a Jordan-Polya number, since it can be written as 8! ⋅ 2!.

It is an interprime number because it is at equal distance from previous prime (80629) and next prime (80651).

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

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

It is an Ulam number.

It is an unprimeable number.

80640 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 11 ways as a sum of consecutive naturals, for example, 11517 + ... + 11523.

280640 is an apocalyptic number.

80640 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 80640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159432).

80640 is an abundant number, since it is smaller than the sum of its proper divisors (238224).

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

80640 is a wasteful number, since it uses less digits than its factorization.

80640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 80640 is about 283.9718295888. The cubic root of 80640 is about 43.2032919302.

The spelling of 80640 in words is "eighty thousand, six hundred forty".

Divisors: 1 2 3 4 5 6 7 8 9 10 12 14 15 16 18 20 21 24 28 30 32 35 36 40 42 45 48 56 60 63 64 70 72 80 84 90 96 105 112 120 126 128 140 144 160 168 180 192 210 224 240 252 256 280 288 315 320 336 360 384 420 448 480 504 560 576 630 640 672 720 768 840 896 960 1008 1120 1152 1260 1280 1344 1440 1680 1792 1920 2016 2240 2304 2520 2688 2880 3360 3840 4032 4480 5040 5376 5760 6720 8064 8960 10080 11520 13440 16128 20160 26880 40320 80640