663444 has 24 divisors (see below), whose sum is σ = 1720320. Its totient is φ = 221112.

The previous prime is 663437. The next prime is 663463. The reversal of 663444 is 444366.

It is a happy number.

663444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×663444² = 880315882272, which contains 22 as substring.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a plaindrome in base 14.

It is a congruent number.

It is an unprimeable number.

663444 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2964 + ... + 3179.

It is an arithmetic number, because the mean of its divisors is an integer number (71680).

2⁶⁶³⁴⁴⁴ is an apocalyptic number.

It is an amenable number.

663444 is an abundant number, since it is smaller than the sum of its proper divisors (1056876).

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

663444 is a wasteful number, since it uses less digits than its factorization.

663444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6156 (or 6148 counting only the distinct ones).

The product of its digits is 6912, while the sum is 27.

The square root of 663444 is about 814.5207179685. The cubic root of 663444 is about 87.2170561143.

The spelling of 663444 in words is "six hundred sixty-three thousand, four hundred forty-four".