855505559 has 2 divisors, whose sum is σ = 855505560. Its totient is φ = 855505558.

The previous prime is 855505529. The next prime is 855505561. The reversal of 855505559 is 955505558.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 855505559 - 2²⁰ = 854456983 is a prime.

It is a super-2 number, since 2×855505559² = 1463779522959804962, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 855505561, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (855505529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 427752779 + 427752780.

It is an arithmetic number, because the mean of its divisors is an integer number (427752780).

Almost surely, 2^855505559 is an apocalyptic number.

855505559 is a deficient number, since it is larger than the sum of its proper divisors (1).

855505559 is an equidigital number, since it uses as much as digits as its factorization.

855505559 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1125000, while the sum is 47.

The square root of 855505559 is about 29249.0266333770. The cubic root of 855505559 is about 949.3090299638.

Subtracting 855505559 from its reverse (955505558), we obtain a palindrome (99999999).

The spelling of 855505559 in words is "eight hundred fifty-five million, five hundred five thousand, five hundred fifty-nine".