663895440 has 480 divisors, whose sum is σ = 2593334016. Its totient is φ = 156764160.

The previous prime is 663895433. The next prime is 663895487. The reversal of 663895440 is 44598366.

663895440 is a `hidden beast` number, since 6 + 638 + 9 + 5 + 4 + 4 + 0 = 666.

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 95 ways as a sum of consecutive naturals, for example, 9350605 + ... + 9350675.

Almost surely, 2^663895440 is an apocalyptic number.

663895440 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 663895440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1296667008).

663895440 is an abundant number, since it is smaller than the sum of its proper divisors (1929438576).

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

663895440 is a wasteful number, since it uses less digits than its factorization.

663895440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The square root of 663895440 is about 25766.1685160988. The cubic root of 663895440 is about 872.3683389042.

The spelling of 663895440 in words is "six hundred sixty-three million, eight hundred ninety-five thousand, four hundred forty".