663858 has 24 divisors (see below), whose sum is σ = 1549548. Its totient is φ = 204192.

The previous prime is 663857. The next prime is 663869. The reversal of 663858 is 858366.

It can be written as a sum of positive squares in 2 ways, for example, as 514089 + 149769 = 717^2 + 387^2 .

It is a d-powerful number, because it can be written as 6³ + 6³ + 8⁴ + 3⁸ + 5⁸ + 8⁶ .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 663858.

It is not an unprimeable number, because it can be changed into a prime (663853) 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 11 ways as a sum of consecutive naturals, for example, 1185 + ... + 1652.

2⁶⁶³⁸⁵⁸ is an apocalyptic number.

663858 is an abundant number, since it is smaller than the sum of its proper divisors (885690).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

663858 is a wasteful number, since it uses less digits than its factorization.

663858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2858 (or 2855 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 663858 is about 814.7748155165. The cubic root of 663858 is about 87.2351939693.

It can be divided in two parts, 663 and 858, that added together give a square (1521 = 39²).

The spelling of 663858 in words is "six hundred sixty-three thousand, eight hundred fifty-eight".