520640137 has 2 divisors, whose sum is σ = 520640138. Its totient is φ = 520640136.

The previous prime is 520640129. The next prime is 520640143. The reversal of 520640137 is 731046025.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 443481481 + 77158656 = 21059^2 + 8784^2 .

It is a cyclic number.

It is not a de Polignac number, because 520640137 - 2³ = 520640129 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (520640537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260320068 + 260320069.

It is an arithmetic number, because the mean of its divisors is an integer number (260320069).

Almost surely, 2^520640137 is an apocalyptic number.

It is an amenable number.

520640137 is a deficient number, since it is larger than the sum of its proper divisors (1).

520640137 is an equidigital number, since it uses as much as digits as its factorization.

520640137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 520640137 is about 22817.5401171993. The cubic root of 520640137 is about 804.4749927302.

The spelling of 520640137 in words is "five hundred twenty million, six hundred forty thousand, one hundred thirty-seven".