521369 has 2 divisors, whose sum is σ = 521370. Its totient is φ = 521368.

The previous prime is 521363. The next prime is 521377. The reversal of 521369 is 963125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 405769 + 115600 = 637^2 + 340^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521369 is a prime.

It is a super-2 number, since 2×521369² = 543651268322, which contains 22 as substring.

It is a Chen prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 521369.

It is not a weakly prime, because it can be changed into another prime (521363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260684 + 260685.

It is an arithmetic number, because the mean of its divisors is an integer number (260685).

2⁵²¹³⁶⁹ is an apocalyptic number.

It is an amenable number.

521369 is a deficient number, since it is larger than the sum of its proper divisors (1).

521369 is an equidigital number, since it uses as much as digits as its factorization.

521369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1620, while the sum is 26.

The square root of 521369 is about 722.0588618665. The cubic root of 521369 is about 80.4850222253.

The spelling of 521369 in words is "five hundred twenty-one thousand, three hundred sixty-nine".