647468640 has 672 divisors, whose sum is σ = 2868941376. Its totient is φ = 134369280.

The previous prime is 647468629. The next prime is 647468683. The reversal of 647468640 is 46864746.

It is a tau number, because it is divible by the number of its divisors (672).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 10614210 + ... + 10614270.

It is an arithmetic number, because the mean of its divisors is an integer number (4269258).

Almost surely, 2^647468640 is an apocalyptic number.

647468640 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 647468640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1434470688).

647468640 is an abundant number, since it is smaller than the sum of its proper divisors (2221472736).

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

647468640 is a wasteful number, since it uses less digits than its factorization.

647468640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 45.

The square root of 647468640 is about 25445.4050861840. The cubic root of 647468640 is about 865.1131485742.

The spelling of 647468640 in words is "six hundred forty-seven million, four hundred sixty-eight thousand, six hundred forty".