825551 has 2 divisors, whose sum is σ = 825552. Its totient is φ = 825550.

The previous prime is 825547. The next prime is 825553. The reversal of 825551 is 155528.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 825551 - 2² = 825547 is a prime.

Together with 825553, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 825551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (825553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 412775 + 412776.

It is an arithmetic number, because the mean of its divisors is an integer number (412776).

2⁸²⁵⁵⁵¹ is an apocalyptic number.

825551 is a deficient number, since it is larger than the sum of its proper divisors (1).

825551 is an equidigital number, since it uses as much as digits as its factorization.

825551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2000, while the sum is 26.

The square root of 825551 is about 908.5983711189. The cubic root of 825551 is about 93.8097479879.

The spelling of 825551 in words is "eight hundred twenty-five thousand, five hundred fifty-one".