647983221 has 8 divisors (see below), whose sum is σ = 893770080. Its totient is φ = 417092592.

The previous prime is 647983159. The next prime is 647983243. The reversal of 647983221 is 122389746.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 647983221 - 2⁶ = 647983157 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647983261) 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 7 ways as a sum of consecutive naturals, for example, 3723955 + ... + 3724128.

It is an arithmetic number, because the mean of its divisors is an integer number (111721260).

Almost surely, 2^647983221 is an apocalyptic number.

It is an amenable number.

647983221 is a deficient number, since it is larger than the sum of its proper divisors (245786859).

647983221 is a wasteful number, since it uses less digits than its factorization.

647983221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7448115.

The product of its digits is 145152, while the sum is 42.

The square root of 647983221 is about 25455.5145498966. The cubic root of 647983221 is about 865.3422731368.

The spelling of 647983221 in words is "six hundred forty-seven million, nine hundred eighty-three thousand, two hundred twenty-one".