520207861 has 2 divisors, whose sum is σ = 520207862. Its totient is φ = 520207860.

The previous prime is 520207847. The next prime is 520207907. The reversal of 520207861 is 168702025.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 305585361 + 214622500 = 17481^2 + 14650^2 .

It is a cyclic number.

It is not a de Polignac number, because 520207861 - 2⁷ = 520207733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (520207801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260103930 + 260103931.

It is an arithmetic number, because the mean of its divisors is an integer number (260103931).

Almost surely, 2^520207861 is an apocalyptic number.

It is an amenable number.

520207861 is a deficient number, since it is larger than the sum of its proper divisors (1).

520207861 is an equidigital number, since it uses as much as digits as its factorization.

520207861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 520207861 is about 22808.0657005367. The cubic root of 520207861 is about 804.2522851463.

Adding to 520207861 its reverse (168702025), we get a palindrome (688909886).

The spelling of 520207861 in words is "five hundred twenty million, two hundred seven thousand, eight hundred sixty-one".