663566400 has 504 divisors, whose sum is σ = 2800624320. Its totient is φ = 145797120.

The previous prime is 663566383. The next prime is 663566419. The reversal of 663566400 is 4665366.

663566400 is a `hidden beast` number, since 6 + 6 + 3 + 5 + 6 + 640 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (504).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2923087 + ... + 2923313.

Almost surely, 2^663566400 is an apocalyptic number.

663566400 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 663566400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1400312160).

663566400 is an abundant number, since it is smaller than the sum of its proper divisors (2137057920).

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

663566400 is a wasteful number, since it uses less digits than its factorization.

663566400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The square root of 663566400 is about 25759.7826077784. The cubic root of 663566400 is about 872.2241939603.

The spelling of 663566400 in words is "six hundred sixty-three million, five hundred sixty-six thousand, four hundred".