663544 has 48 divisors (see below), whose sum is σ = 1547280. Its totient is φ = 261120.

The previous prime is 663541. The next prime is 663547. The reversal of 663544 is 445366.

It is an interprime number because it is at equal distance from previous prime (663541) and next prime (663547).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a zygodrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663541) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16164 + ... + 16204.

It is an arithmetic number, because the mean of its divisors is an integer number (32235).

2⁶⁶³⁵⁴⁴ 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 663544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (773640).

663544 is an abundant number, since it is smaller than the sum of its proper divisors (883736).

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

663544 is a wasteful number, since it uses less digits than its factorization.

663544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 67 counting only the distinct ones).

The product of its digits is 8640, while the sum is 28.

The square root of 663544 is about 814.5821014483. The cubic root of 663544 is about 87.2214379297.

The spelling of 663544 in words is "six hundred sixty-three thousand, five hundred forty-four".