840405605 has 32 divisors (see below), whose sum is σ = 1121132544. Its totient is φ = 600742656.

The previous prime is 840405593. The next prime is 840405613. The reversal of 840405605 is 506504048.

It is not a de Polignac number, because 840405605 - 2⁶ = 840405541 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 535532 + ... + 537098.

It is an arithmetic number, because the mean of its divisors is an integer number (35035392).

Almost surely, 2^840405605 is an apocalyptic number.

It is an amenable number.

840405605 is a deficient number, since it is larger than the sum of its proper divisors (280726939).

840405605 is a wasteful number, since it uses less digits than its factorization.

840405605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845.

The product of its (nonzero) digits is 19200, while the sum is 32.

The square root of 840405605 is about 28989.7499989220. The cubic root of 840405605 is about 943.6906383141.

The spelling of 840405605 in words is "eight hundred forty million, four hundred five thousand, six hundred five".