5555 has 8 divisors (see below), whose sum is σ = 7344. Its totient is φ = 4000.

The previous prime is 5531. The next prime is 5557.

5555 = T₄₀ + T₄₁ + ... + T₄₅.

It is a happy number.

5555 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 5555 - 2¹² = 1459 is a prime.

It is a nude number because it is divisible by every one of its digits.

It is a Duffinian number.

5555 is a modest number, since divided by 555 gives 5 as remainder.

5555 is a nontrivial repdigit in base 10.

It is a plaindrome in base 10.

It is a nialpdrome in base 9 and base 10.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (5557) by changing a digit.

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, 5 + ... + 105.

It is an arithmetic number, because the mean of its divisors is an integer number (918).

2⁵⁵⁵⁵ is an apocalyptic number.

5555 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

5555 is a deficient number, since it is larger than the sum of its proper divisors (1789).

5555 is a wasteful number, since it uses less digits than its factorization.

5555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117.

The product of its digits is 625, while the sum is 20.

The square root of 5555 is about 74.5318723769. The cubic root of 5555 is about 17.7103857675.

It can be divided in two parts, 555 and 5, that multiplied together give a triangular number (2775 = T₇₄).

The spelling of 5555 in words is "five thousand, five hundred fifty-five".