505455561 has 24 divisors (see below), whose sum is σ = 787026240. Its totient is φ = 310748256.

The previous prime is 505455553. The next prime is 505455581. The reversal of 505455561 is 165554505.

505455561 is a `hidden beast` number, since 5 + 0 + 545 + 55 + 61 = 666.

It is not a de Polignac number, because 505455561 - 2³ = 505455553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (505455581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 214930 + ... + 217268.

It is an arithmetic number, because the mean of its divisors is an integer number (32792760).

Almost surely, 2^505455561 is an apocalyptic number.

It is an amenable number.

505455561 is a deficient number, since it is larger than the sum of its proper divisors (281570679).

505455561 is a wasteful number, since it uses less digits than its factorization.

505455561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4205 (or 4202 counting only the distinct ones).

The product of its (nonzero) digits is 75000, while the sum is 36.

The square root of 505455561 is about 22482.3388685430. The cubic root of 505455561 is about 796.5768111359.

The spelling of 505455561 in words is "five hundred five million, four hundred fifty-five thousand, five hundred sixty-one".