647221072 has 80 divisors (see below), whose sum is σ = 1335628800. Its totient is φ = 303367680.

The previous prime is 647221051. The next prime is 647221103. The reversal of 647221072 is 270122746.

647221072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3388497 + ... + 3388687.

It is an arithmetic number, because the mean of its divisors is an integer number (16695360).

Almost surely, 2^647221072 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 647221072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (667814400).

647221072 is an abundant number, since it is smaller than the sum of its proper divisors (688407728).

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

647221072 is a wasteful number, since it uses less digits than its factorization.

647221072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404 (or 398 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 31.

The square root of 647221072 is about 25440.5399313772. The cubic root of 647221072 is about 865.0028721212.

The spelling of 647221072 in words is "six hundred forty-seven million, two hundred twenty-one thousand, seventy-two".