663445 has 4 divisors (see below), whose sum is σ = 796140. Its totient is φ = 530752.

The previous prime is 663437. The next prime is 663463. The reversal of 663445 is 544366.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 544366 = 2 ⋅272183.

It can be written as a sum of positive squares in 2 ways, for example, as 106929 + 556516 = 327^2 + 746^2 .

It is a cyclic number.

It is not a de Polignac number, because 663445 - 2³ = 663437 is a prime.

It is a plaindrome in base 14.

It is a congruent number.

It is an unprimeable number.

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, 66340 + ... + 66349.

It is an arithmetic number, because the mean of its divisors is an integer number (199035).

2⁶⁶³⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

663445 is a deficient number, since it is larger than the sum of its proper divisors (132695).

663445 is a wasteful number, since it uses less digits than its factorization.

663445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132694.

The product of its digits is 8640, while the sum is 28.

The square root of 663445 is about 814.5213318262. The cubic root of 663445 is about 87.2170999346.

The spelling of 663445 in words is "six hundred sixty-three thousand, four hundred forty-five".