• 555 = F5+5+5 + F5+5, where Fk denotes the k-th Fibonacci number.
555 has 8
divisors (see below), whose sum is σ = 912
Its totient is φ = 288
The previous prime is 547. The next prime is 557.
555 is nontrivially palindromic in base 9, base 10 and base 12.
555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
555 is an esthetic number in base 6 and base 9, because in such bases its adjacent digits differ by 1.
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 555 - 23 = 547 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (15), and also a Moran number because the ratio is a prime number: 37 = 555 / (5 + 5 + 5).
It is a nude number because it is divisible by every one of its digits.
555 is an undulating number in base 6, base 9 and base 12.
555 is a modest number, since divided by 55 gives 5 as remainder.
555 is a nontrivial repdigit in base 10.
It is a plaindrome in base 10, base 13 and base 16.
It is a nialpdrome in base 5 and base 10.
It is a zygodrome in base 10.
It is not an unprimeable number, because it can be changed into a prime (557) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is an upside-down number.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4 + ... + 33.
It is an arithmetic number, because the mean of its divisors is an integer number (114).
555 is a deficient number, since it is larger than the sum of its proper divisors (357).
555 is a wasteful number, since it uses less digits than its factorization.
555 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 45.
The product of its digits is 125, while the sum is 15.
The square root of 555 is about 23.5584379788.
The cubic root of 555 is about 8.2179657649.
The spelling of 555 in words is "five hundred fifty-five", and thus it is an aban number and an oban number.