9998401988400 has 2160 divisors, whose sum is σ = 41325731269632. Its totient is φ = 2022556262400.

The previous prime is 9998401988389. The next prime is 9998401988401. The reversal of 9998401988400 is 48891048999.

It is not an unprimeable number, because it can be changed into a prime (9998401988401) by changing a digit.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 136964410764 + ... + 136964410836.

Almost surely, 2^{9998401988400} 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 9998401988400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20662865634816).

9998401988400 is an abundant number, since it is smaller than the sum of its proper divisors (31327329281232).

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

9998401988400 is a wasteful number, since it uses less digits than its factorization.

9998401988400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 53747712, while the sum is 69.

The spelling of 9998401988400 in words is "nine trillion, nine hundred ninety-eight billion, four hundred one million, nine hundred eighty-eight thousand, four hundred".