663663840 has 384 divisors, whose sum is σ = 2540160000. Its totient is φ = 145410048.

The previous prime is 663663839. The next prime is 663663851. The reversal of 663663840 is 48366366.

663663840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×663663840³ (a number of 27 digits) contains 333 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 663663792 and 663663801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4774491 + ... + 4774629.

It is an arithmetic number, because the mean of its divisors is an integer number (6615000).

Almost surely, 2^663663840 is an apocalyptic number.

663663840 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 663663840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1270080000).

663663840 is an abundant number, since it is smaller than the sum of its proper divisors (1876496160).

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

663663840 is a wasteful number, since it uses less digits than its factorization.

663663840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207 (or 185 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 42.

The square root of 663663840 is about 25761.6738586607. The cubic root of 663663840 is about 872.2668851744.

The spelling of 663663840 in words is "six hundred sixty-three million, six hundred sixty-three thousand, eight hundred forty".