9939866400 has 216 divisors, whose sum is σ = 36349329744. Its totient is φ = 2650579200.

The previous prime is 9939866399. The next prime is 9939866483. The reversal of 9939866400 is 46689399.

It is a happy number.

9939866400 is a `hidden beast` number, since 9 + 93 + 98 + 66 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (216).

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

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 168835 + ... + 219965.

It is an arithmetic number, because the mean of its divisors is an integer number (168283934).

Almost surely, 2^9939866400 is an apocalyptic number.

9939866400 is a gapful number since it is divisible by the number (90) 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 9939866400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18174664872).

9939866400 is an abundant number, since it is smaller than the sum of its proper divisors (26409463344).

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

9939866400 is a wasteful number, since it uses less digits than its factorization.

9939866400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51166 (or 51141 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The square root of 9939866400 is about 99698.8786296014. The cubic root of 9939866400 is about 2150.1075410423.

The spelling of 9939866400 in words is "nine billion, nine hundred thirty-nine million, eight hundred sixty-six thousand, four hundred".