663942 has 16 divisors (see below), whose sum is σ = 1336320. Its totient is φ = 219912.

The previous prime is 663937. The next prime is 663959. The reversal of 663942 is 249366.

It is a d-powerful number, because it can be written as 6² + 6⁴ + 9² + 3¹² + 4² + 2¹⁷ .

It is a congruent number.

It is an unprimeable number.

663942 is an untouchable number, because it is not equal to the sum of proper divisors of any 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 7 ways as a sum of consecutive naturals, for example, 1203 + ... + 1665.

It is an arithmetic number, because the mean of its divisors is an integer number (83520).

2⁶⁶³⁹⁴² is an apocalyptic number.

663942 is an abundant number, since it is smaller than the sum of its proper divisors (672378).

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

663942 is a wasteful number, since it uses less digits than its factorization.

663942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707.

The product of its digits is 7776, while the sum is 30.

The square root of 663942 is about 814.8263618710. The cubic root of 663942 is about 87.2388731935.

The spelling of 663942 in words is "six hundred sixty-three thousand, nine hundred forty-two".