663642 has 48 divisors (see below), whose sum is σ = 1722240. Its totient is φ = 180576.

The previous prime is 663631. The next prime is 663653. The reversal of 663642 is 246366.

It is an interprime number because it is at equal distance from previous prime (663631) and next prime (663653).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 2784 + ... + 3012.

It is an arithmetic number, because the mean of its divisors is an integer number (35880).

2⁶⁶³⁶⁴² is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (861120).

663642 is an abundant number, since it is smaller than the sum of its proper divisors (1058598).

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

663642 is a wasteful number, since it uses less digits than its factorization.

663642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267 (or 264 counting only the distinct ones).

The product of its digits is 5184, while the sum is 27.

The square root of 663642 is about 814.6422527711. The cubic root of 663642 is about 87.2257316817.

It can be divided in two parts, 66364 and 2, that added together give a palindrome (66366).

The spelling of 663642 in words is "six hundred sixty-three thousand, six hundred forty-two".