647353728 has 128 divisors (see below), whose sum is σ = 2183616000. Its totient is φ = 184951296.

The previous prime is 647353711. The next prime is 647353741. The reversal of 647353728 is 827353746.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 10813 + ... + 37571.

It is an arithmetic number, because the mean of its divisors is an integer number (17059500).

Almost surely, 2^647353728 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 647353728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1091808000).

647353728 is an abundant number, since it is smaller than the sum of its proper divisors (1536262272).

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

647353728 is a wasteful number, since it uses less digits than its factorization.

647353728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26789 (or 26771 counting only the distinct ones).

The product of its digits is 846720, while the sum is 45.

The square root of 647353728 is about 25443.1469751680. The cubic root of 647353728 is about 865.0619657793.

The spelling of 647353728 in words is "six hundred forty-seven million, three hundred fifty-three thousand, seven hundred twenty-eight".