647893 has 2 divisors, whose sum is σ = 647894. Its totient is φ = 647892.

The previous prime is 647891. The next prime is 647909. The reversal of 647893 is 398746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 628849 + 19044 = 793^2 + 138^2 .

It is a cyclic number.

It is not a de Polignac number, because 647893 - 2¹ = 647891 is a prime.

Together with 647891, it forms a pair of twin primes.

647893 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323946 + 323947.

It is an arithmetic number, because the mean of its divisors is an integer number (323947).

2⁶⁴⁷⁸⁹³ is an apocalyptic number.

It is an amenable number.

647893 is a deficient number, since it is larger than the sum of its proper divisors (1).

647893 is an equidigital number, since it uses as much as digits as its factorization.

647893 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 37.

The square root of 647893 is about 804.9180082468. The cubic root of 647893 is about 86.5302109716.

It can be divided in two parts, 647 and 893, that added together give a triangular number (1540 = T₅₅).

The spelling of 647893 in words is "six hundred forty-seven thousand, eight hundred ninety-three".