6840109 has 2 divisors, whose sum is σ = 6840110. Its totient is φ = 6840108.

The previous prime is 6840091. The next prime is 6840157. The reversal of 6840109 is 9010486.

Together with previous prime (6840091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4818025 + 2022084 = 2195^2 + 1422^2 .

It is a cyclic number.

It is not a de Polignac number, because 6840109 - 2¹⁵ = 6807341 is a prime.

It is a super-2 number, since 2×6840109² = 93574182263762, which contains 22 as substring.

6840109 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6840179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3420054 + 3420055.

It is an arithmetic number, because the mean of its divisors is an integer number (3420055).

Almost surely, 2^6840109 is an apocalyptic number.

It is an amenable number.

6840109 is a deficient number, since it is larger than the sum of its proper divisors (1).

6840109 is an equidigital number, since it uses as much as digits as its factorization.

6840109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 6840109 is about 2615.3602046372. The cubic root of 6840109 is about 189.8254074817.

The spelling of 6840109 in words is "six million, eight hundred forty thousand, one hundred nine".