999999550550575 has 24 divisors (see below), whose sum is σ = 1240808108452352. Its totient is φ = 799477957530720.

The previous prime is 999999550550437. The next prime is 999999550550597. The reversal of 999999550550575 is 575055055999999.

999999550550575 is a nontrivial binomial coefficient, being equal to C(44721350, 2).

It is not a de Polignac number, because 999999550550575 - 2²⁵ = 999999516996143 is a prime.

It is a super-2 number, since 2×999999550550575² (a number of 31 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 999999550550575.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1117586512 + ... + 1118480938.

Almost surely, 2^{999999550550575} is an apocalyptic number.

999999550550575 is the 44721349-th triangular number and also the 22360675-th hexagonal number.

999999550550575 is the 14907117-th centered nonagonal number.

999999550550575 is a deficient number, since it is larger than the sum of its proper divisors (240808557901777).

999999550550575 is a wasteful number, since it uses less digits than its factorization.

999999550550575 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 923551 (or 923546 counting only the distinct ones).

The product of its (nonzero) digits is 58126359375, while the sum is 91.

The spelling of 999999550550575 in words is "nine hundred ninety-nine trillion, nine hundred ninety-nine billion, five hundred fifty million, five hundred fifty thousand, five hundred seventy-five".