647686368 has 288 divisors, whose sum is σ = 2226422016. Its totient is φ = 181398528.

The previous prime is 647686357. The next prime is 647686381. The reversal of 647686368 is 863686746.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3973455 + ... + 3973617.

It is an arithmetic number, because the mean of its divisors is an integer number (7730632).

Almost surely, 2^647686368 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 647686368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1113211008).

647686368 is an abundant number, since it is smaller than the sum of its proper divisors (1578735648).

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

647686368 is a wasteful number, since it uses less digits than its factorization.

647686368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268 (or 248 counting only the distinct ones).

The product of its digits is 6967296, while the sum is 54.

The square root of 647686368 is about 25449.6830628595. The cubic root of 647686368 is about 865.2101098963.

The spelling of 647686368 in words is "six hundred forty-seven million, six hundred eighty-six thousand, three hundred sixty-eight".