663780 has 96 divisors (see below), whose sum is σ = 2145024. Its totient is φ = 152064.

The previous prime is 663763. The next prime is 663787. The reversal of 663780 is 87366.

It is a Harshad number since it is a multiple of its sum of digits (30).

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 31 ways as a sum of consecutive naturals, for example, 17922 + ... + 17958.

It is an arithmetic number, because the mean of its divisors is an integer number (22344).

2⁶⁶³⁷⁸⁰ is an apocalyptic number.

663780 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1072512).

663780 is an abundant number, since it is smaller than the sum of its proper divisors (1481244).

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

663780 is a wasteful number, since it uses less digits than its factorization.

663780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 663780 is about 814.7269481243. The cubic root of 663780 is about 87.2317772689.

The spelling of 663780 in words is "six hundred sixty-three thousand, seven hundred eighty".