840105 has 48 divisors (see below), whose sum is σ = 1751040. Its totient is φ = 381024.

The previous prime is 840083. The next prime is 840109. The reversal of 840105 is 501048.

840105 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 840105 - 2¹³ = 831913 is a prime.

It is a super-2 number, since 2×840105² = 1411552822050, which contains 22 as substring.

840105 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 840105.

It is not an unprimeable number, because it can be changed into a prime (840109) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6552 + ... + 6678.

It is an arithmetic number, because the mean of its divisors is an integer number (36480).

2⁸⁴⁰¹⁰⁵ is an apocalyptic number.

It is an amenable number.

840105 is an abundant number, since it is smaller than the sum of its proper divisors (910935).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

840105 is a wasteful number, since it uses less digits than its factorization.

840105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 840105 is about 916.5724193974. The cubic root of 840105 is about 94.3578108542.

The spelling of 840105 in words is "eight hundred forty thousand, one hundred five".