840478689 has 12 divisors (see below), whose sum is σ = 1220128000. Its totient is φ = 557502264.

The previous prime is 840478669. The next prime is 840478729. The reversal of 840478689 is 986874048.

840478689 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 840478689 - 2²⁰ = 839430113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (840478669) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 232849 + ... + 236430.

Almost surely, 2^840478689 is an apocalyptic number.

It is an amenable number.

840478689 is a deficient number, since it is larger than the sum of its proper divisors (379649311).

840478689 is a wasteful number, since it uses less digits than its factorization.

840478689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469484 (or 469481 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 54.

The square root of 840478689 is about 28991.0104860110. The cubic root of 840478689 is about 943.7179928387.

The spelling of 840478689 in words is "eight hundred forty million, four hundred seventy-eight thousand, six hundred eighty-nine".