No
42
SMITH Numbers
- 728 has a digit sum of 7+2+8=17. It's
Prime factorisation is 2x2x2x7x13. The sum of the digits of thses
prime factors is 2+2+2+7+1+3=17 the same as the digit sum. So 728
is a SMITH Number. The smallest Smith Number is 4. Check that 22,
27 and 58 are the next three Smith Numbers. There are two moire
Smith Numbers less than 100, can you find them?
- 728 and 729 are called Smith
Brothers... check their prime factorisations. The smallest set of
three Smith Brothers is 73615, 73616 and 73618....amazing!
- (Smith numbers are named after Harold
Smith who had a telephone number 4937775 ...)
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