647439 has 12 divisors (see below), whose sum is σ = 935496. Its totient is φ = 398112.

The previous prime is 647429. The next prime is 647441. The reversal of 647439 is 934746.

647439 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 647439 - 2⁹ = 646927 is a prime.

647439 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 647439.

It is not an unprimeable number, because it can be changed into a prime (647429) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 132 + ... + 1145.

It is an arithmetic number, because the mean of its divisors is an integer number (77958).

2⁶⁴⁷⁴³⁹ is an apocalyptic number.

647439 is a deficient number, since it is larger than the sum of its proper divisors (288057).

647439 is a wasteful number, since it uses less digits than its factorization.

647439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1306 (or 1293 counting only the distinct ones).

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

The square root of 647439 is about 804.6359425231. The cubic root of 647439 is about 86.5099947242.

It can be divided in two parts, 64 and 7439, that added together give a triangular number (7503 = T₁₂₂).

The spelling of 647439 in words is "six hundred forty-seven thousand, four hundred thirty-nine".