509039681 has 2 divisors, whose sum is σ = 509039682. Its totient is φ = 509039680.

The previous prime is 509039651. The next prime is 509039711. The reversal of 509039681 is 186930905.

It is a balanced prime because it is at equal distance from previous prime (509039651) and next prime (509039711).

It can be written as a sum of positive squares in only one way, i.e., 458345281 + 50694400 = 21409^2 + 7120^2 .

It is a cyclic number.

It is not a de Polignac number, because 509039681 - 2⁶ = 509039617 is a prime.

It is a super-4 number, since 4×509039681⁴ (a number of 36 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (509039651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254519840 + 254519841.

It is an arithmetic number, because the mean of its divisors is an integer number (254519841).

Almost surely, 2^509039681 is an apocalyptic number.

It is an amenable number.

509039681 is a deficient number, since it is larger than the sum of its proper divisors (1).

509039681 is an equidigital number, since it uses as much as digits as its factorization.

509039681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 509039681 is about 22561.9077429193. The cubic root of 509039681 is about 798.4551860449.

The spelling of 509039681 in words is "five hundred nine million, thirty-nine thousand, six hundred eighty-one".