509056821 has 48 divisors (see below), whose sum is σ = 918596224. Its totient is φ = 264477312.

The previous prime is 509056819. The next prime is 509056837. The reversal of 509056821 is 128650905.

It is a happy number.

509056821 is a `hidden beast` number, since 5 + 0 + 90 + 568 + 2 + 1 = 666.

It is not a de Polignac number, because 509056821 - 2¹ = 509056819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (509056021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 50235 + ... + 59511.

Almost surely, 2^509056821 is an apocalyptic number.

It is an amenable number.

509056821 is a deficient number, since it is larger than the sum of its proper divisors (409539403).

509056821 is a wasteful number, since it uses less digits than its factorization.

509056821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9370 (or 9367 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 509056821 is about 22562.2875834876. The cubic root of 509056821 is about 798.4641476045.

The spelling of 509056821 in words is "five hundred nine million, fifty-six thousand, eight hundred twenty-one".