520961729 has 2 divisors, whose sum is σ = 520961730. Its totient is φ = 520961728.

The previous prime is 520961711. The next prime is 520961731. The reversal of 520961729 is 927169025.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 388090000 + 132871729 = 19700^2 + 11527^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-520961729 is a prime.

It is a super-2 number, since 2×520961729² = 542802246165338882, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 520961731, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (520961759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260480864 + 260480865.

It is an arithmetic number, because the mean of its divisors is an integer number (260480865).

Almost surely, 2^520961729 is an apocalyptic number.

It is an amenable number.

520961729 is a deficient number, since it is larger than the sum of its proper divisors (1).

520961729 is an equidigital number, since it uses as much as digits as its factorization.

520961729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 68040, while the sum is 41.

The square root of 520961729 is about 22824.5860641546. The cubic root of 520961729 is about 804.6405962210.

The spelling of 520961729 in words is "five hundred twenty million, nine hundred sixty-one thousand, seven hundred twenty-nine".