646044440 has 32 divisors (see below), whose sum is σ = 1463240160. Its totient is φ = 256704000.

The previous prime is 646044439. The next prime is 646044449. The reversal of 646044440 is 44440646.

It is a junction number, because it is equal to n+sod(n) for n = 646044397 and 646044406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646044449) 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, 47441 + ... + 59520.

It is an arithmetic number, because the mean of its divisors is an integer number (45726255).

Almost surely, 2^646044440 is an apocalyptic number.

It is an amenable number.

646044440 is an abundant number, since it is smaller than the sum of its proper divisors (817195720).

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

646044440 is a wasteful number, since it uses less digits than its factorization.

646044440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107123 (or 107119 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 32.

The square root of 646044440 is about 25417.4042734501. The cubic root of 646044440 is about 864.4783694952.

The spelling of 646044440 in words is "six hundred forty-six million, forty-four thousand, four hundred forty".