## Harshad numberA number that is divisible by the sum of its own digits. For example, 1729 is a Harshad number because 1 + 7 + 2 + 9 = 19 and 1729 = 19 × 91. Harshad numbers are also known as Niven numbers.A Harshad amicable pair is an amicable
pair (m, n) such that both m and n are Harshad
numbers. For example, 2620 and 2924 are a Harshad amicable pair because
2620 is divisible by 2 + 6 + 2 + 0 = 10 and 2924 is divisible by 2 + 9 +
2 + 4 = 17 (2924/17 = 172). There are 192 Harshad amicable pairs in first
5,000 amicable pairs. ## Related category• TYPES OF NUMBERS | |||||

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