511530021 has 24 divisors (see below), whose sum is σ = 760965920. Its totient is φ = 330928416.

The previous prime is 511530013. The next prime is 511530031. The reversal of 511530021 is 120035115.

It is not a de Polignac number, because 511530021 - 2³ = 511530013 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 511529976 and 511530003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (511530031) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56550 + ... + 64968.

Almost surely, 2^511530021 is an apocalyptic number.

It is an amenable number.

511530021 is a deficient number, since it is larger than the sum of its proper divisors (249435899).

511530021 is a wasteful number, since it uses less digits than its factorization.

511530021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8625 (or 8622 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 511530021 is about 22617.0294468571. The cubic root of 511530021 is about 799.7551443356.

Adding to 511530021 its reverse (120035115), we get a palindrome (631565136).

The spelling of 511530021 in words is "five hundred eleven million, five hundred thirty thousand, twenty-one".