8475821 has 2 divisors, whose sum is σ = 8475822. Its totient is φ = 8475820.

The previous prime is 8475793. The next prime is 8475823. The reversal of 8475821 is 1285748.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7761796 + 714025 = 2786^2 + 845^2 .

It is a cyclic number.

It is not a de Polignac number, because 8475821 - 2⁶ = 8475757 is a prime.

It is a Sophie Germain prime.

Together with 8475823, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8475823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4237910 + 4237911.

It is an arithmetic number, because the mean of its divisors is an integer number (4237911).

Almost surely, 2^8475821 is an apocalyptic number.

It is an amenable number.

8475821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8475821 is an equidigital number, since it uses as much as digits as its factorization.

8475821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17920, while the sum is 35.

The square root of 8475821 is about 2911.3263300427. The cubic root of 8475821 is about 203.8890608514.

The spelling of 8475821 in words is "eight million, four hundred seventy-five thousand, eight hundred twenty-one".