663837720 has 512 divisors, whose sum is σ = 2647572480. Its totient is φ = 129392640.

The previous prime is 663837703. The next prime is 663837721. The reversal of 663837720 is 27738366.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663837721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 12525214 + ... + 12525266.

It is an arithmetic number, because the mean of its divisors is an integer number (5171040).

Almost surely, 2^663837720 is an apocalyptic number.

663837720 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 663837720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1323786240).

663837720 is an abundant number, since it is smaller than the sum of its proper divisors (1983734760).

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

663837720 is a wasteful number, since it uses less digits than its factorization.

663837720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 42.

The square root of 663837720 is about 25765.0484183516. The cubic root of 663837720 is about 872.3430565295.

The spelling of 663837720 in words is "six hundred sixty-three million, eight hundred thirty-seven thousand, seven hundred twenty".