825446821 has 2 divisors, whose sum is σ = 825446822. Its totient is φ = 825446820.

The previous prime is 825446819. The next prime is 825446873. The reversal of 825446821 is 128644528.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 816530625 + 8916196 = 28575^2 + 2986^2 .

It is a cyclic number.

It is not a de Polignac number, because 825446821 - 2¹ = 825446819 is a prime.

Together with 825446819, 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 (825441821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 412723410 + 412723411.

It is an arithmetic number, because the mean of its divisors is an integer number (412723411).

Almost surely, 2^825446821 is an apocalyptic number.

It is an amenable number.

825446821 is a deficient number, since it is larger than the sum of its proper divisors (1).

825446821 is an equidigital number, since it uses as much as digits as its factorization.

825446821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 122880, while the sum is 40.

The square root of 825446821 is about 28730.5903350418. The cubic root of 825446821 is about 938.0580176818.

The spelling of 825446821 in words is "eight hundred twenty-five million, four hundred forty-six thousand, eight hundred twenty-one".