647863 has 4 divisors (see below), whose sum is σ = 654640. Its totient is φ = 641088.

The previous prime is 647861. The next prime is 647891. The reversal of 647863 is 368746.

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 647863 - 2¹ = 647861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647861) 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, 3243 + ... + 3436.

It is an arithmetic number, because the mean of its divisors is an integer number (163660).

2⁶⁴⁷⁸⁶³ is an apocalyptic number.

647863 is a deficient number, since it is larger than the sum of its proper divisors (6777).

647863 is an equidigital number, since it uses as much as digits as its factorization.

647863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6776.

The product of its digits is 24192, while the sum is 34.

The square root of 647863 is about 804.8993725926. The cubic root of 647863 is about 86.5288753877.

The spelling of 647863 in words is "six hundred forty-seven thousand, eight hundred sixty-three".