663969600 has 378 divisors, whose sum is σ = 2748112614. Its totient is φ = 151603200.

The previous prime is 663969599. The next prime is 663969613. The reversal of 663969600 is 6969366.

663969600 is a `hidden beast` number, since 6 + 6 + 39 + 6 + 9 + 600 = 666.

663969600 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 62346816 + 601622784 = 7896^2 + 24528^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 705130 + ... + 706070.

Almost surely, 2^663969600 is an apocalyptic number.

663969600 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663969600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1374056307).

663969600 is an abundant number, since it is smaller than the sum of its proper divisors (2084143014).

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

663969600 is a wasteful number, since it uses less digits than its factorization.

663969600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 983 (or 958 counting only the distinct ones).

The product of its (nonzero) digits is 314928, while the sum is 45.

The square root of 663969600 is about 25767.6075722990. The cubic root of 663969600 is about 872.4008201371.

The spelling of 663969600 in words is "six hundred sixty-three million, nine hundred sixty-nine thousand, six hundred".