Hoax number

A kind of number

About Hoax number

A hoax number is a composite number for which the sum of the digits of n equals the sum of the digits of its distinct prime factors (each factor counted once). Unlike Smith numbers, multiplicity is ignored.

Key features

  • Example: 22 = 2 × 11; digits 2+2 = 4, distinct factors 2 and 11 give 2+1+1 = 4.
  • Primes are excluded (no composite factorization).

Examples:

22, 84, 234, 265, 266, 285, 294, 348, 357, 382, 385, 423, 436, 438, 453

Further reading