869021 has 2 divisors, whose sum is σ = 869022. Its totient is φ = 869020.

The previous prime is 869017. The next prime is 869039. The reversal of 869021 is 120968.

869021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 525625 + 343396 = 725^2 + 586^2 .

It is a cyclic number.

It is not a de Polignac number, because 869021 - 2² = 869017 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (869081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 434510 + 434511.

It is an arithmetic number, because the mean of its divisors is an integer number (434511).

2⁸⁶⁹⁰²¹ is an apocalyptic number.

It is an amenable number.

869021 is a deficient number, since it is larger than the sum of its proper divisors (1).

869021 is an equidigital number, since it uses as much as digits as its factorization.

869021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 869021 is about 932.2129585025. The cubic root of 869021 is about 95.4282054995.

Adding to 869021 its reverse (120968), we get a palindrome (989989).

The spelling of 869021 in words is "eight hundred sixty-nine thousand, twenty-one".