840078423 has 12 divisors (see below), whose sum is σ = 1239265248. Its totient is φ = 548136000.

The previous prime is 840078419. The next prime is 840078439. The reversal of 840078423 is 324870048.

It is not a de Polignac number, because 840078423 - 2² = 840078419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840078223) 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 in 11 ways as a sum of consecutive naturals, for example, 992578 + ... + 993423.

It is an arithmetic number, because the mean of its divisors is an integer number (103272104).

Almost surely, 2^840078423 is an apocalyptic number.

840078423 is a deficient number, since it is larger than the sum of its proper divisors (399186825).

840078423 is a wasteful number, since it uses less digits than its factorization.

840078423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1986054 (or 1986051 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The square root of 840078423 is about 28984.1063860868. The cubic root of 840078423 is about 943.5681583016.

The spelling of 840078423 in words is "eight hundred forty million, seventy-eight thousand, four hundred twenty-three".