875821 has 2 divisors, whose sum is σ = 875822. Its totient is φ = 875820.

The previous prime is 875803. The next prime is 875837. The reversal of 875821 is 128578.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 509796 + 366025 = 714^2 + 605^2 .

It is a cyclic number.

It is not a de Polignac number, because 875821 - 2¹¹ = 873773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (875851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 437910 + 437911.

It is an arithmetic number, because the mean of its divisors is an integer number (437911).

2⁸⁷⁵⁸²¹ is an apocalyptic number.

It is an amenable number.

875821 is a deficient number, since it is larger than the sum of its proper divisors (1).

875821 is an equidigital number, since it uses as much as digits as its factorization.

875821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4480, while the sum is 31.

The square root of 875821 is about 935.8530867610. The cubic root of 875821 is about 95.6764643874.

The spelling of 875821 in words is "eight hundred seventy-five thousand, eight hundred twenty-one".