509646816 has 168 divisors, whose sum is σ = 1719822384. Its totient is φ = 145566720.

The previous prime is 509646773. The next prime is 509646821. The reversal of 509646816 is 618646905.

509646816 is a `hidden beast` number, since 509 + 64 + 6 + 81 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 161736 + ... + 164856.

It is an arithmetic number, because the mean of its divisors is an integer number (10237038).

Almost surely, 2^509646816 is an apocalyptic number.

509646816 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 509646816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (859911192).

509646816 is an abundant number, since it is smaller than the sum of its proper divisors (1210175568).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

509646816 is an equidigital number, since it uses as much as digits as its factorization.

509646816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3156 (or 3133 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 509646816 is about 22575.3586018030. The cubic root of 509646816 is about 798.7725008539.

The spelling of 509646816 in words is "five hundred nine million, six hundred forty-six thousand, eight hundred sixteen".