665447 has 2 divisors, whose sum is σ = 665448. Its totient is φ = 665446.

The previous prime is 665429. The next prime is 665479. The reversal of 665447 is 744566.

It is an a-pointer prime, because the next prime (665479) can be obtained adding 665447 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665447 - 2¹⁴ = 649063 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665047) 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, 332723 + 332724.

It is an arithmetic number, because the mean of its divisors is an integer number (332724).

2⁶⁶⁵⁴⁴⁷ is an apocalyptic number.

665447 is a deficient number, since it is larger than the sum of its proper divisors (1).

665447 is an equidigital number, since it uses as much as digits as its factorization.

665447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 32.

The square root of 665447 is about 815.7493487586. The cubic root of 665447 is about 87.3047401037.

The spelling of 665447 in words is "six hundred sixty-five thousand, four hundred forty-seven".