505439999 has 4 divisors (see below), whose sum is σ = 507065520. Its totient is φ = 503814480.

The previous prime is 505439993. The next prime is 505440007. The reversal of 505439999 is 999934505.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999934505 = 5 ⋅199986901.

It is a cyclic number.

It is not a de Polignac number, because 505439999 - 2²⁸ = 237004543 is a prime.

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 505439999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505439993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 812294 + ... + 812915.

It is an arithmetic number, because the mean of its divisors is an integer number (126766380).

Almost surely, 2^505439999 is an apocalyptic number.

505439999 is a deficient number, since it is larger than the sum of its proper divisors (1625521).

505439999 is a wasteful number, since it uses less digits than its factorization.

505439999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1625520.

The product of its (nonzero) digits is 1968300, while the sum is 53.

The square root of 505439999 is about 22481.9927719942. The cubic root of 505439999 is about 796.5686360317.

The spelling of 505439999 in words is "five hundred five million, four hundred thirty-nine thousand, nine hundred ninety-nine".