509985913 has 4 divisors (see below), whose sum is σ = 511033600. Its totient is φ = 508938228.

The previous prime is 509985901. The next prime is 509985919. The reversal of 509985913 is 319589905.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 509985913 - 2⁵ = 509985881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (509985919) 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, 523113 + ... + 524086.

It is an arithmetic number, because the mean of its divisors is an integer number (127758400).

Almost surely, 2^509985913 is an apocalyptic number.

It is an amenable number.

509985913 is a deficient number, since it is larger than the sum of its proper divisors (1047687).

509985913 is a wasteful number, since it uses less digits than its factorization.

509985913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1047686.

The product of its (nonzero) digits is 437400, while the sum is 49.

The square root of 509985913 is about 22582.8676876964. The cubic root of 509985913 is about 798.9496178294.

The spelling of 509985913 in words is "five hundred nine million, nine hundred eighty-five thousand, nine hundred thirteen".