840468639 has 8 divisors (see below), whose sum is σ = 1120900480. Its totient is φ = 560174616.

The previous prime is 840468623. The next prime is 840468649. The reversal of 840468639 is 936864048.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 840468639 - 2⁴ = 840468623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840468619) 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 7 ways as a sum of consecutive naturals, for example, 19267 + ... + 45300.

It is an arithmetic number, because the mean of its divisors is an integer number (140112560).

Almost surely, 2^840468639 is an apocalyptic number.

840468639 is a deficient number, since it is larger than the sum of its proper divisors (280431841).

840468639 is a wasteful number, since it uses less digits than its factorization.

840468639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68909.

The product of its (nonzero) digits is 995328, while the sum is 48.

The square root of 840468639 is about 28990.8371559015. The cubic root of 840468639 is about 943.7142313301.

The spelling of 840468639 in words is "eight hundred forty million, four hundred sixty-eight thousand, six hundred thirty-nine".