840478705631 has 32 divisors (see below), whose sum is σ = 905321775360. Its totient is φ = 777903388416.

The previous prime is 840478705613. The next prime is 840478705639. The reversal of 840478705631 is 136507874048.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 840478705631 - 2¹⁸ = 840478443487 is a prime.

It is a super-2 number, since 2×840478705631² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840478705639) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 300491525 + ... + 300494321.

It is an arithmetic number, because the mean of its divisors is an integer number (28291305480).

Almost surely, 2^840478705631 is an apocalyptic number.

840478705631 is a deficient number, since it is larger than the sum of its proper divisors (64843069729).

840478705631 is a wasteful number, since it uses less digits than its factorization.

840478705631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4743.

The product of its (nonzero) digits is 4515840, while the sum is 53.

The spelling of 840478705631 in words is "eight hundred forty billion, four hundred seventy-eight million, seven hundred five thousand, six hundred thirty-one".