663949 has 8 divisors (see below), whose sum is σ = 780192. Its totient is φ = 557040.

The previous prime is 663937. The next prime is 663959. The reversal of 663949 is 949366.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 663949 - 2⁷ = 663821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663959) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2179 + ... + 2464.

It is an arithmetic number, because the mean of its divisors is an integer number (97524).

2⁶⁶³⁹⁴⁹ is an apocalyptic number.

It is an amenable number.

663949 is a deficient number, since it is larger than the sum of its proper divisors (116243).

663949 is a wasteful number, since it uses less digits than its factorization.

663949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4667.

The product of its digits is 34992, while the sum is 37.

The square root of 663949 is about 814.8306572534. The cubic root of 663949 is about 87.2391797815.

The spelling of 663949 in words is "six hundred sixty-three thousand, nine hundred forty-nine".