663616 has 14 divisors (see below), whose sum is σ = 1316990. Its totient is φ = 331776.

The previous prime is 663601. The next prime is 663631. The reversal of 663616 is 616366.

It is an interprime number because it is at equal distance from previous prime (663601) and next prime (663631).

It can be written as a sum of positive squares in only one way, i.e., 409600 + 254016 = 640^2 + 504^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5121 + ... + 5248.

2⁶⁶³⁶¹⁶ is an apocalyptic number.

It is an amenable number.

663616 is a deficient number, since it is larger than the sum of its proper divisors (653374).

663616 is a wasteful number, since it uses less digits than its factorization.

663616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10381 (or 10371 counting only the distinct ones).

The product of its digits is 3888, while the sum is 28.

The square root of 663616 is about 814.6262946898. The cubic root of 663616 is about 87.2245925642.

The spelling of 663616 in words is "six hundred sixty-three thousand, six hundred sixteen".