505005055551 has 12 divisors (see below), whose sum is σ = 729476295912. Its totient is φ = 336658706736.

The previous prime is 505005055549. The next prime is 505005055573. The reversal of 505005055551 is 155550500505.

It is a happy number.

505005055551 is a `hidden beast` number, since 5 + 0 + 5 + 0 + 0 + 50 + 55 + 551 = 666.

It is not a de Polignac number, because 505005055551 - 2¹ = 505005055549 is a prime.

It is a super-2 number, since 2×505005055551² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505005055591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 657321 + ... + 1200866.

It is an arithmetic number, because the mean of its divisors is an integer number (60789691326).

Almost surely, 2^505005055551 is an apocalyptic number.

505005055551 is a deficient number, since it is larger than the sum of its proper divisors (224471240361).

505005055551 is a wasteful number, since it uses less digits than its factorization.

505005055551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1888390 (or 1888387 counting only the distinct ones).

The product of its (nonzero) digits is 78125, while the sum is 36.

The spelling of 505005055551 in words is "five hundred five billion, five million, fifty-five thousand, five hundred fifty-one".