555 (number)

← 554 555 556 →
List of numbers; Integers; ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	five hundred fifty-five
Ordinal	555th; (five hundred fifty-fifth)
Factorization	3 × 5 × 37
Greek numeral	ΦΝΕ´
Roman numeral	DLV
Binary	10001010112
Ternary	2021203
Senary	23236
Octal	10538
Duodecimal	3A312
Hexadecimal	22B16

555 (five hundred [and] fifty-five) is the natural number following 554 and preceding 556.

In mathematics

555 is a sphenic number. In base 10, it is a repdigit, and because it is divisible by the sum of its digits, it is a Harshad number. It is also a Harshad number in binary, base 11, base 13 and hexadecimal.

It is the sum of the first triplet of three-digit permutable primes in decimal:

113+131+311=555

.

It is the twenty-sixth number such that its Euler totient (288) is equal to the totient value of its sum-of-divisors: $\varphi (555)=\varphi (\sigma (555))$ .^[1]

References

^ Sloane, N. J. A. (ed.). "Sequence A006872 (Numbers k such that phi(k) is phi(sigma(k)).)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2023-08-31.

External links

Media related to 555 (number) at Wikimedia Commons

[1] Sloane, N. J. A. (ed.). "Sequence A006872 (Numbers k such that phi(k) is phi(sigma(k)).)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2023-08-31.

[1]