521960069 has 2 divisors, whose sum is σ = 521960070. Its totient is φ = 521960068.

The previous prime is 521959943. The next prime is 521960071. The reversal of 521960069 is 960069125.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 481802500 + 40157569 = 21950^2 + 6337^2 .

It is a cyclic number.

It is not a de Polignac number, because 521960069 - 2²⁸ = 253524613 is a prime.

It is a super-2 number, since 2×521960069² = 544884627260969522, which contains 22 as substring.

Together with 521960071, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521960869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260980034 + 260980035.

It is an arithmetic number, because the mean of its divisors is an integer number (260980035).

Almost surely, 2^521960069 is an apocalyptic number.

It is an amenable number.

521960069 is a deficient number, since it is larger than the sum of its proper divisors (1).

521960069 is an equidigital number, since it uses as much as digits as its factorization.

521960069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 521960069 is about 22846.4454346841. The cubic root of 521960069 is about 805.1542566676.

The spelling of 521960069 in words is "five hundred twenty-one million, nine hundred sixty thousand, sixty-nine".