663980 has 12 divisors (see below), whose sum is σ = 1394400. Its totient is φ = 265584.

The previous prime is 663979. The next prime is 663983. The reversal of 663980 is 89366.

It is a happy number.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 663980.

It is not an unprimeable number, because it can be changed into a prime (663983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16580 + ... + 16619.

It is an arithmetic number, because the mean of its divisors is an integer number (116200).

2⁶⁶³⁹⁸⁰ is an apocalyptic number.

It is an amenable number.

663980 is an abundant number, since it is smaller than the sum of its proper divisors (730420).

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

663980 is a wasteful number, since it uses less digits than its factorization.

663980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33208 (or 33206 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 663980 is about 814.8496793888. The cubic root of 663980 is about 87.2405375025.

The spelling of 663980 in words is "six hundred sixty-three thousand, nine hundred eighty".