505551009999 has 48 divisors (see below), whose sum is σ = 811044299520. Its totient is φ = 279103628160.

The previous prime is 505551009961. The next prime is 505551010067. The reversal of 505551009999 is 999900155505.

It is not a de Polignac number, because 505551009999 - 2¹³ = 505551001807 is a prime.

It is a super-2 number, since 2×505551009999² (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 (505551009919) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 213592 + ... + 1027970.

It is an arithmetic number, because the mean of its divisors is an integer number (16896756240).

Almost surely, 2^505551009999 is an apocalyptic number.

505551009999 is a deficient number, since it is larger than the sum of its proper divisors (305493289521).

505551009999 is a wasteful number, since it uses less digits than its factorization.

505551009999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 814540 (or 814533 counting only the distinct ones).

The product of its (nonzero) digits is 4100625, while the sum is 57.

The spelling of 505551009999 in words is "five hundred five billion, five hundred fifty-one million, nine thousand, nine hundred ninety-nine".