663559 has 4 divisors (see below), whose sum is σ = 714616. Its totient is φ = 612504.

The previous prime is 663557. The next prime is 663563. The reversal of 663559 is 955366.

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

It is a cyclic number.

It is not a de Polignac number, because 663559 - 2¹ = 663557 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 (663557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25509 + ... + 25534.

It is an arithmetic number, because the mean of its divisors is an integer number (178654).

2⁶⁶³⁵⁵⁹ is an apocalyptic number.

663559 is a deficient number, since it is larger than the sum of its proper divisors (51057).

663559 is a wasteful number, since it uses less digits than its factorization.

663559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51056.

The product of its digits is 24300, while the sum is 34.

The square root of 663559 is about 814.5913085714. The cubic root of 663559 is about 87.2220951641. Note that the first 3 decimals are identical.

The spelling of 663559 in words is "six hundred sixty-three thousand, five hundred fifty-nine".