520840069 has 2 divisors, whose sum is σ = 520840070. Its totient is φ = 520840068.

The previous prime is 520840003. The next prime is 520840093. The reversal of 520840069 is 960048025.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 520524225 + 315844 = 22815^2 + 562^2 .

It is a cyclic number.

It is not a de Polignac number, because 520840069 - 2¹³ = 520831877 is a prime.

It is a super-2 number, since 2×520840069² = 542548754951849522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (520840469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260420034 + 260420035.

It is an arithmetic number, because the mean of its divisors is an integer number (260420035).

Almost surely, 2^520840069 is an apocalyptic number.

It is an amenable number.

520840069 is a deficient number, since it is larger than the sum of its proper divisors (1).

520840069 is an equidigital number, since it uses as much as digits as its factorization.

520840069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 520840069 is about 22821.9207999677. The cubic root of 520840069 is about 804.5779555376.

The spelling of 520840069 in words is "five hundred twenty million, eight hundred forty thousand, sixty-nine".