663786 has 12 divisors (see below), whose sum is σ = 1438242. Its totient is φ = 221256.

The previous prime is 663763. The next prime is 663787. The reversal of 663786 is 687366.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 447561 + 216225 = 669^2 + 465^2 .

It is a super-2 number, since 2×663786² = 881223707592, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 663786.

It is not an unprimeable number, because it can be changed into a prime (663787) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18421 + ... + 18456.

2⁶⁶³⁷⁸⁶ is an apocalyptic number.

663786 is an abundant number, since it is smaller than the sum of its proper divisors (774456).

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

663786 is a wasteful number, since it uses less digits than its factorization.

663786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36885 (or 36882 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 663786 is about 814.7306303313. The cubic root of 663786 is about 87.2320401015.

The spelling of 663786 in words is "six hundred sixty-three thousand, seven hundred eighty-six".