663717 has 4 divisors (see below), whose sum is σ = 884960. Its totient is φ = 442476.

The previous prime is 663713. The next prime is 663737. The reversal of 663717 is 717366.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 663717 - 2² = 663713 is a prime.

It is a D-number.

It is a Duffinian number.

663717 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110617 + ... + 110622.

It is an arithmetic number, because the mean of its divisors is an integer number (221240).

2⁶⁶³⁷¹⁷ is an apocalyptic number.

It is an amenable number.

663717 is a deficient number, since it is larger than the sum of its proper divisors (221243).

663717 is a wasteful number, since it uses less digits than its factorization.

663717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221242.

The product of its digits is 5292, while the sum is 30.

The square root of 663717 is about 814.6882839467. The cubic root of 663717 is about 87.2290174309.

The spelling of 663717 in words is "six hundred sixty-three thousand, seven hundred seventeen".