663784 has 32 divisors (see below), whose sum is σ = 1432800. Its totient is φ = 285120.

The previous prime is 663763. The next prime is 663787. The reversal of 663784 is 487366.

It is not an unprimeable number, because it can be changed into a prime (663787) 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 7 ways as a sum of consecutive naturals, for example, 1474 + ... + 1870.

It is an arithmetic number, because the mean of its divisors is an integer number (44775).

2⁶⁶³⁷⁸⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (716400).

663784 is an abundant number, since it is smaller than the sum of its proper divisors (769016).

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

663784 is a wasteful number, since it uses less digits than its factorization.

663784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 433 (or 429 counting only the distinct ones).

The product of its digits is 24192, while the sum is 34.

The square root of 663784 is about 814.7294029308. The cubic root of 663784 is about 87.2319524908.

The spelling of 663784 in words is "six hundred sixty-three thousand, seven hundred eighty-four".