840075644 has 24 divisors (see below), whose sum is σ = 1548143520. Its totient is φ = 398084544.

The previous prime is 840075641. The next prime is 840075653. The reversal of 840075644 is 446570048.

It is a junction number, because it is equal to n+sod(n) for n = 840075598 and 840075607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840075641) 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, 31859 + ... + 51914.

It is an arithmetic number, because the mean of its divisors is an integer number (64505980).

Almost surely, 2^840075644 is an apocalyptic number.

It is an amenable number.

840075644 is a deficient number, since it is larger than the sum of its proper divisors (708067876).

840075644 is a wasteful number, since it uses less digits than its factorization.

840075644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83909 (or 83907 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 38.

The square root of 840075644 is about 28984.0584459803. The cubic root of 840075644 is about 943.5671178515.

The spelling of 840075644 in words is "eight hundred forty million, seventy-five thousand, six hundred forty-four".