506557809 has 6 divisors (see below), whose sum is σ = 731694626. Its totient is φ = 337705200.

The previous prime is 506557783. The next prime is 506557813. The reversal of 506557809 is 908755605.

It can be written as a sum of positive squares in only one way, i.e., 490179600 + 16378209 = 22140^2 + 4047^2 .

It is not a de Polignac number, because 506557809 - 2¹¹ = 506555761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (506557609) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 28142092 + ... + 28142109.

Almost surely, 2^506557809 is an apocalyptic number.

It is an amenable number.

506557809 is a deficient number, since it is larger than the sum of its proper divisors (225136817).

506557809 is a wasteful number, since it uses less digits than its factorization.

506557809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56284207 (or 56284204 counting only the distinct ones).

The product of its (nonzero) digits is 378000, while the sum is 45.

The square root of 506557809 is about 22506.8391605752. The cubic root of 506557809 is about 797.1554229860.

The spelling of 506557809 in words is "five hundred six million, five hundred fifty-seven thousand, eight hundred nine".