555555999 has 16 divisors (see below), whose sum is σ = 762994400. Its totient is φ = 359303040.

The previous prime is 555555967. The next prime is 555556021. The reversal of 555555999 is 999555555.

555555999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 555555999 - 2⁵ = 555555967 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (555555199) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31569 + ... + 45909.

It is an arithmetic number, because the mean of its divisors is an integer number (47687150).

Almost surely, 2^555555999 is an apocalyptic number.

555555999 is a deficient number, since it is larger than the sum of its proper divisors (207438401).

555555999 is a wasteful number, since it uses less digits than its factorization.

555555999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14730.

The product of its digits is 11390625, while the sum is 57.

The square root of 555555999 is about 23570.2354464269. The cubic root of 555555999 is about 822.0709101690.

The spelling of 555555999 in words is "five hundred fifty-five million, five hundred fifty-five thousand, nine hundred ninety-nine".