9966403944 has 256 divisors, whose sum is σ = 33723648000. Its totient is φ = 2697043392.

The previous prime is 9966403891. The next prime is 9966403957. The reversal of 9966403944 is 4493046699.

9966403944 is a `hidden beast` number, since 99 + 66 + 403 + 94 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

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, 2324827 + ... + 2329109.

It is an arithmetic number, because the mean of its divisors is an integer number (131733000).

Almost surely, 2^9966403944 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9966403944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16861824000).

9966403944 is an abundant number, since it is smaller than the sum of its proper divisors (23757244056).

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

9966403944 is a wasteful number, since it uses less digits than its factorization.

9966403944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4336 (or 4314 counting only the distinct ones).

The product of its (nonzero) digits is 5038848, while the sum is 54.

The square root of 9966403944 is about 99831.8783956307. The cubic root of 9966403944 is about 2152.0192994727.

The spelling of 9966403944 in words is "nine billion, nine hundred sixty-six million, four hundred three thousand, nine hundred forty-four".