520240909 has 2 divisors, whose sum is σ = 520240910. Its totient is φ = 520240908.

The previous prime is 520240907. The next prime is 520240913. The reversal of 520240909 is 909042025.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 489382884 + 30858025 = 22122^2 + 5555^2 .

It is a cyclic number.

It is not a de Polignac number, because 520240909 - 2¹ = 520240907 is a prime.

Together with 520240907, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (520240907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260120454 + 260120455.

It is an arithmetic number, because the mean of its divisors is an integer number (260120455).

Almost surely, 2^520240909 is an apocalyptic number.

It is an amenable number.

520240909 is a deficient number, since it is larger than the sum of its proper divisors (1).

520240909 is an equidigital number, since it uses as much as digits as its factorization.

520240909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 520240909 is about 22808.7901695816. The cubic root of 520240909 is about 804.2693157532.

The spelling of 520240909 in words is "five hundred twenty million, two hundred forty thousand, nine hundred nine".