520728389977 has 2 divisors, whose sum is σ = 520728389978. Its totient is φ = 520728389976.

The previous prime is 520728389939. The next prime is 520728390019. The reversal of 520728389977 is 779983827025.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 487903647001 + 32824742976 = 698501^2 + 181176^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-520728389977 is a prime.

It is a super-2 number, since 2×520728389977² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (520728389477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260364194988 + 260364194989.

It is an arithmetic number, because the mean of its divisors is an integer number (260364194989).

Almost surely, 2^520728389977 is an apocalyptic number.

It is an amenable number.

520728389977 is a deficient number, since it is larger than the sum of its proper divisors (1).

520728389977 is an equidigital number, since it uses as much as digits as its factorization.

520728389977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 106686720, while the sum is 67.

The spelling of 520728389977 in words is "five hundred twenty billion, seven hundred twenty-eight million, three hundred eighty-nine thousand, nine hundred seventy-seven".