2121972318400 has 1344 divisors, whose sum is σ = 6514683033600. Its totient is φ = 671514624000.

The previous prime is 2121972318371. The next prime is 2121972318413. The reversal of 2121972318400 is 48132791212.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 23842385556 + ... + 23842385644.

It is an arithmetic number, because the mean of its divisors is an integer number (4847234400).

Almost surely, 2^{2121972318400} is an apocalyptic number.

2121972318400 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 2121972318400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3257341516800).

2121972318400 is an abundant number, since it is smaller than the sum of its proper divisors (4392710715200).

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

2121972318400 is a wasteful number, since it uses less digits than its factorization.

2121972318400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 251 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 40.

The spelling of 2121972318400 in words is "two trillion, one hundred twenty-one billion, nine hundred seventy-two million, three hundred eighteen thousand, four hundred".