509619905 has 4 divisors (see below), whose sum is σ = 611543892. Its totient is φ = 407695920.

The previous prime is 509619883. The next prime is 509619923. The reversal of 509619905 is 509916905.

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 198697216 + 310922689 = 14096^2 + 17633^2 .

It is not a de Polignac number, because 509619905 - 2¹⁰ = 509618881 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50961986 + ... + 50961995.

It is an arithmetic number, because the mean of its divisors is an integer number (152885973).

Almost surely, 2^509619905 is an apocalyptic number.

It is an amenable number.

509619905 is a deficient number, since it is larger than the sum of its proper divisors (101923987).

509619905 is a wasteful number, since it uses less digits than its factorization.

509619905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101923986.

The product of its (nonzero) digits is 109350, while the sum is 44.

The square root of 509619905 is about 22574.7625679651. The cubic root of 509619905 is about 798.7584413494.

The spelling of 509619905 in words is "five hundred nine million, six hundred nineteen thousand, nine hundred five".