821069 has 2 divisors, whose sum is σ = 821070. Its totient is φ = 821068.

The previous prime is 821063. The next prime is 821081. The reversal of 821069 is 960128.

821069 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., 504100 + 316969 = 710^2 + 563^2 .

It is a cyclic number.

It is not a de Polignac number, because 821069 - 2⁴ = 821053 is a prime.

It is a super-2 number, since 2×821069² = 1348308605522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 821069.

It is not a weakly prime, because it can be changed into another prime (821063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410534 + 410535.

It is an arithmetic number, because the mean of its divisors is an integer number (410535).

2⁸²¹⁰⁶⁹ is an apocalyptic number.

It is an amenable number.

821069 is a deficient number, since it is larger than the sum of its proper divisors (1).

821069 is an equidigital number, since it uses as much as digits as its factorization.

821069 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 821069 is about 906.1285780727. The cubic root of 821069 is about 93.6396722882.

The spelling of 821069 in words is "eight hundred twenty-one thousand, sixty-nine".