840636468 has 120 divisors (see below), whose sum is σ = 2659390272. Its totient is φ = 226043136.

The previous prime is 840636443. The next prime is 840636469. The reversal of 840636468 is 864636048.

840636468 is a `hidden beast` number, since 8 + 4 + 0 + 636 + 4 + 6 + 8 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840636469) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 27655 + ... + 49457.

Almost surely, 2^840636468 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 840636468, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1329695136).

840636468 is an abundant number, since it is smaller than the sum of its proper divisors (1818753804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

840636468 is a wasteful number, since it uses less digits than its factorization.

840636468 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21843 (or 21832 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The square root of 840636468 is about 28993.7315294186. The cubic root of 840636468 is about 943.7770423490. Note that the first 3 decimals are identical.

The spelling of 840636468 in words is "eight hundred forty million, six hundred thirty-six thousand, four hundred sixty-eight".