9999561236400 has 360 divisors, whose sum is σ = 35087827806720. Its totient is φ = 2636917839360.

The previous prime is 9999561236377. The next prime is 9999561236419. The reversal of 9999561236400 is 46321659999.

9999561236400 is a `hidden beast` number, since 9 + 9 + 9 + 9 + 5 + 612 + 3 + 6 + 4 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 266586447 + ... + 266623953.

It is an arithmetic number, because the mean of its divisors is an integer number (97466188352).

Almost surely, 2^{9999561236400} is an apocalyptic number.

9999561236400 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 9999561236400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17543913903360).

9999561236400 is an abundant number, since it is smaller than the sum of its proper divisors (25088266570320).

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

9999561236400 is a wasteful number, since it uses less digits than its factorization.

9999561236400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38353 (or 38339 counting only the distinct ones).

The product of its (nonzero) digits is 28343520, while the sum is 63.

The spelling of 9999561236400 in words is "nine trillion, nine hundred ninety-nine billion, five hundred sixty-one million, two hundred thirty-six thousand, four hundred".