647667672 has 64 divisors (see below), whose sum is σ = 1747872000. Its totient is φ = 199377024.

The previous prime is 647667667. The next prime is 647667679. The reversal of 647667672 is 276766746.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647667679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4222 + ... + 36237.

It is an arithmetic number, because the mean of its divisors is an integer number (27310500).

Almost surely, 2^647667672 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 647667672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (873936000).

647667672 is an abundant number, since it is smaller than the sum of its proper divisors (1100204328).

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

647667672 is a wasteful number, since it uses less digits than its factorization.

647667672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40520 (or 40516 counting only the distinct ones).

The product of its digits is 3556224, while the sum is 51.

The square root of 647667672 is about 25449.3157471866. The cubic root of 647667672 is about 865.2017848156.

The spelling of 647667672 in words is "six hundred forty-seven million, six hundred sixty-seven thousand, six hundred seventy-two".