840656544 has 288 divisors, whose sum is σ = 2823387840. Its totient is φ = 217018368.

The previous prime is 840656533. The next prime is 840656549. The reversal of 840656544 is 445656048.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 840656496 and 840656505.

It is not an unprimeable number, because it can be changed into a prime (840656549) 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 47 ways as a sum of consecutive naturals, for example, 3607852 + ... + 3608084.

It is an arithmetic number, because the mean of its divisors is an integer number (9803430).

Almost surely, 2^840656544 is an apocalyptic number.

840656544 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 840656544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1411693920).

840656544 is an abundant number, since it is smaller than the sum of its proper divisors (1982731296).

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

840656544 is a wasteful number, since it uses less digits than its factorization.

840656544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 42.

The square root of 840656544 is about 28994.0777401179. The cubic root of 840656544 is about 943.7845553536.

It can be divided in two parts, 84065 and 6544, that added together give a palindrome (90609).

The spelling of 840656544 in words is "eight hundred forty million, six hundred fifty-six thousand, five hundred forty-four".