521000069 has 2 divisors, whose sum is σ = 521000070. Its totient is φ = 521000068.

The previous prime is 521000033. The next prime is 521000093. The reversal of 521000069 is 960000125.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 514699969 + 6300100 = 22687^2 + 2510^2 .

It is a cyclic number.

It is not a de Polignac number, because 521000069 - 2⁸ = 520999813 is a prime.

It is a super-2 number, since 2×521000069² = 542882143796009522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521000269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260500034 + 260500035.

It is an arithmetic number, because the mean of its divisors is an integer number (260500035).

Almost surely, 2^521000069 is an apocalyptic number.

It is an amenable number.

521000069 is a deficient number, since it is larger than the sum of its proper divisors (1).

521000069 is an equidigital number, since it uses as much as digits as its factorization.

521000069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 521000069 is about 22825.4259324990. The cubic root of 521000069 is about 804.6603348198.

The spelling of 521000069 in words is "five hundred twenty-one million, sixty-nine", and thus it is an aban number.