2181559910400 has 1344 divisors, whose sum is σ = 8766622454940. Its totient is φ = 535088332800.

The previous prime is 2181559910363. The next prime is 2181559910417. The reversal of 2181559910400 is 40199551812.

2181559910400 is a `hidden beast` number, since 2 + 1 + 8 + 1 + 5 + 599 + 10 + 40 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 572843114496 + 1608716795904 = 756864^2 + 1268352^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 7763558260 + ... + 7763558540.

Almost surely, 2^{2181559910400} is an apocalyptic number.

2181559910400 is a gapful number since it is divisible by the number (20) 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 2181559910400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4383311227470).

2181559910400 is an abundant number, since it is smaller than the sum of its proper divisors (6585062544540).

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

2181559910400 is an frugal number, since it uses more digits than its factorization.

2181559910400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 45.

The spelling of 2181559910400 in words is "two trillion, one hundred eighty-one billion, five hundred fifty-nine million, nine hundred ten thousand, four hundred".