647965 has 4 divisors (see below), whose sum is σ = 777564. Its totient is φ = 518368.

The previous prime is 647963. The next prime is 647987. The reversal of 647965 is 569746.

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

It can be written as a sum of positive squares in 2 ways, for example, as 181476 + 466489 = 426^2 + 683^2 .

It is a cyclic number.

It is not a de Polignac number, because 647965 - 2¹ = 647963 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 (647963) 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 in 3 ways as a sum of consecutive naturals, for example, 64792 + ... + 64801.

It is an arithmetic number, because the mean of its divisors is an integer number (194391).

2⁶⁴⁷⁹⁶⁵ is an apocalyptic number.

It is an amenable number.

647965 is a deficient number, since it is larger than the sum of its proper divisors (129599).

647965 is a wasteful number, since it uses less digits than its factorization.

647965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129598.

The product of its digits is 45360, while the sum is 37.

The square root of 647965 is about 804.9627320566. The cubic root of 647965 is about 86.5334162047.

The spelling of 647965 in words is "six hundred forty-seven thousand, nine hundred sixty-five".