663679 has 8 divisors (see below), whose sum is σ = 696320. Its totient is φ = 631800.

The previous prime is 663661. The next prime is 663683. The reversal of 663679 is 976366.

663679 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 663679 - 2⁹ = 663167 is a prime.

It is a d-powerful number, because it can be written as 6² + 6³ + 6⁵ + 3¹² + 7⁶ + 9⁴ .

It is a Duffinian number.

663679 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663659) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2314 + ... + 2584.

It is an arithmetic number, because the mean of its divisors is an integer number (87040).

2⁶⁶³⁶⁷⁹ is an apocalyptic number.

663679 is a deficient number, since it is larger than the sum of its proper divisors (32641).

663679 is a wasteful number, since it uses less digits than its factorization.

663679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381.

The product of its digits is 40824, while the sum is 37.

The square root of 663679 is about 814.6649618095. The cubic root of 663679 is about 87.2273526823.

The spelling of 663679 in words is "six hundred sixty-three thousand, six hundred seventy-nine".