999999505 has 4 divisors (see below), whose sum is σ = 1199999412. Its totient is φ = 799999600.

The previous prime is 999999503. The next prime is 999999527. The reversal of 999999505 is 505999999.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 341769169 + 658230336 = 18487^2 + 25656^2 .

It is not a de Polignac number, because 999999505 - 2¹ = 999999503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999999503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99999946 + ... + 99999955.

It is an arithmetic number, because the mean of its divisors is an integer number (299999853).

Almost surely, 2^999999505 is an apocalyptic number.

It is an amenable number.

999999505 is a deficient number, since it is larger than the sum of its proper divisors (199999907).

999999505 is a wasteful number, since it uses less digits than its factorization.

999999505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199999906.

The product of its (nonzero) digits is 13286025, while the sum is 64.

The square root of 999999505 is about 31622.7687750456. The cubic root of 999999505 is about 999.9998350000. Note that the first 3 decimals are identical.

The spelling of 999999505 in words is "nine hundred ninety-nine million, nine hundred ninety-nine thousand, five hundred five".