509012021 has 16 divisors (see below), whose sum is σ = 595230720. Its totient is φ = 426204720.

The previous prime is 509012017. The next prime is 509012039. The reversal of 509012021 is 120210905.

It is a cyclic number.

It is not a de Polignac number, because 509012021 - 2² = 509012017 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 509011984 and 509012002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (509012051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 226220 + ... + 228458.

It is an arithmetic number, because the mean of its divisors is an integer number (37201920).

Almost surely, 2^509012021 is an apocalyptic number.

It is an amenable number.

509012021 is a deficient number, since it is larger than the sum of its proper divisors (86218699).

509012021 is a wasteful number, since it uses less digits than its factorization.

509012021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2984.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 509012021 is about 22561.2947545126. The cubic root of 509012021 is about 798.4407237340.

Adding to 509012021 its reverse (120210905), we get a palindrome (629222926).

The spelling of 509012021 in words is "five hundred nine million, twelve thousand, twenty-one".