840239012639 has 4 divisors (see below), whose sum is σ = 904872782856. Its totient is φ = 775605242424.

The previous prime is 840239012629. The next prime is 840239012663. The reversal of 840239012639 is 936210932048.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 840239012639 - 2³⁶ = 771519535903 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 840239012593 and 840239012602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840239012629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32316885089 + ... + 32316885114.

It is an arithmetic number, because the mean of its divisors is an integer number (226218195714).

Almost surely, 2^840239012639 is an apocalyptic number.

840239012639 is a deficient number, since it is larger than the sum of its proper divisors (64633770217).

840239012639 is a wasteful number, since it uses less digits than its factorization.

840239012639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64633770216.

The product of its (nonzero) digits is 559872, while the sum is 47.

The spelling of 840239012639 in words is "eight hundred forty billion, two hundred thirty-nine million, twelve thousand, six hundred thirty-nine".