647792640 has 480 divisors, whose sum is σ = 2568646080. Its totient is φ = 154828800.

The previous prime is 647792627. The next prime is 647792657. The reversal of 647792640 is 46297746.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 9123805 + ... + 9123875.

It is an arithmetic number, because the mean of its divisors is an integer number (5351346).

Almost surely, 2^647792640 is an apocalyptic number.

647792640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 647792640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1284323040).

647792640 is an abundant number, since it is smaller than the sum of its proper divisors (1920853440).

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

647792640 is a wasteful number, since it uses less digits than its factorization.

647792640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 92 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 45.

The square root of 647792640 is about 25451.7708617691. The cubic root of 647792640 is about 865.2574283644.

The spelling of 647792640 in words is "six hundred forty-seven million, seven hundred ninety-two thousand, six hundred forty".