647943 has 4 divisors (see below), whose sum is σ = 863928. Its totient is φ = 431960.

The previous prime is 647917. The next prime is 647951. The reversal of 647943 is 349746.

647943 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 647943 - 2⁸ = 647687 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647953) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107988 + ... + 107993.

It is an arithmetic number, because the mean of its divisors is an integer number (215982).

2⁶⁴⁷⁹⁴³ is an apocalyptic number.

647943 is a deficient number, since it is larger than the sum of its proper divisors (215985).

647943 is a wasteful number, since it uses less digits than its factorization.

647943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215984.

The product of its digits is 18144, while the sum is 33.

The square root of 647943 is about 804.9490667117. The cubic root of 647943 is about 86.5324368531.

The spelling of 647943 in words is "six hundred forty-seven thousand, nine hundred forty-three".