820834109 has 2 divisors, whose sum is σ = 820834110. Its totient is φ = 820834108.

The previous prime is 820834081. The next prime is 820834177. The reversal of 820834109 is 901438028.

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., 795804100 + 25030009 = 28210^2 + 5003^2 .

It is a cyclic number.

It is not a de Polignac number, because 820834109 - 2²⁴ = 804056893 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820837109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410417054 + 410417055.

It is an arithmetic number, because the mean of its divisors is an integer number (410417055).

Almost surely, 2^820834109 is an apocalyptic number.

It is an amenable number.

820834109 is a deficient number, since it is larger than the sum of its proper divisors (1).

820834109 is an equidigital number, since it uses as much as digits as its factorization.

820834109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 820834109 is about 28650.2025996327. The cubic root of 820834109 is about 936.3074197331.

The spelling of 820834109 in words is "eight hundred twenty million, eight hundred thirty-four thousand, one hundred nine".