420 (number)
 | This article needs additional citations for verification. (June 2016) |
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|---|---|---|---|---|
| Cardinal | four hundred twenty | |||
| Ordinal | 420th (four hundred twentieth) | |||
| Factorization | 22 × 3 × 5 × 7 | |||
| Greek numeral | ΥΚ´ | |||
| Roman numeral | CDXX | |||
| Binary | 1101001002 | |||
| Ternary | 1201203 | |||
| Senary | 15406 | |||
| Octal | 6448 | |||
| Duodecimal | 2B012 | |||
| Hexadecimal | 1A416 | |||
420 is the natural number following 419 and preceding 421.
420 is the sum of four consecutive primes (101 + 103 + 107 + 109). 420 is a zero of the Mertens function[1] and is sparsely totient.[2] It is a pronic number,[3] and the smallest number divisible by the numbers 1 to 7, and as a consequence of that it is a Harshad number in every base from 2 to 10 except base 5. It is a 141-gonal number.
References
- ^ "Sloane's A028442 : Numbers n such that Mertens' function is zero". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-02.
- ^ "Sloane's A036913 : Sparsely totient numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-02.
- ^ "Sloane's A002378 : Oblong (or promic, pronic, or heteromecic) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-02.