826256581 has 2 divisors, whose sum is σ = 826256582. Its totient is φ = 826256580.

The previous prime is 826256579. The next prime is 826256633. The reversal of 826256581 is 185652628.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 720063556 + 106193025 = 26834^2 + 10305^2 .

It is a cyclic number.

It is not a de Polignac number, because 826256581 - 2¹ = 826256579 is a prime.

It is a super-2 number, since 2×826256581² = 1365399875291619122, which contains 22 as substring.

Together with 826256579, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (826256521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 413128290 + 413128291.

It is an arithmetic number, because the mean of its divisors is an integer number (413128291).

Almost surely, 2^826256581 is an apocalyptic number.

It is an amenable number.

826256581 is a deficient number, since it is larger than the sum of its proper divisors (1).

826256581 is an equidigital number, since it uses as much as digits as its factorization.

826256581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 230400, while the sum is 43.

The square root of 826256581 is about 28744.6791771973. The cubic root of 826256581 is about 938.3646611415.

The spelling of 826256581 in words is "eight hundred twenty-six million, two hundred fifty-six thousand, five hundred eighty-one".