826561 has 2 divisors, whose sum is σ = 826562. Its totient is φ = 826560.

The previous prime is 826559. The next prime is 826571. The reversal of 826561 is 165628.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 571536 + 255025 = 756^2 + 505^2 .

It is a cyclic number.

It is not a de Polignac number, because 826561 - 2¹ = 826559 is a prime.

Together with 826559, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (826541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 413280 + 413281.

It is an arithmetic number, because the mean of its divisors is an integer number (413281).

2⁸²⁶⁵⁶¹ is an apocalyptic number.

It is an amenable number.

826561 is a deficient number, since it is larger than the sum of its proper divisors (1).

826561 is an equidigital number, since it uses as much as digits as its factorization.

826561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2880, while the sum is 28.

The square root of 826561 is about 909.1540023560. The cubic root of 826561 is about 93.8479888043.

It can be divided in two parts, 8 and 26561, that added together give a square (26569 = 163²).

The spelling of 826561 in words is "eight hundred twenty-six thousand, five hundred sixty-one".