2121001010000 has 100 divisors (see below), whose sum is σ = 5186001139044. Its totient is φ = 840000000000.

The previous prime is 2121001009997. The next prime is 2121001010003. The reversal of 2121001010000 is 101001212.

It is an interprime number because it is at equal distance from previous prime (2121001009997) and next prime (2121001010003).

It can be written as a sum of positive squares in 10 ways, for example, as 317491679296 + 1803509330704 = 563464^2 + 1342948^2 .

It is a tau number, because it is divible by the number of its divisors (100).

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a self number, because there is not a number n which added to its sum of digits gives 2121001010000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121001010003) by changing a digit.

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 19 ways as a sum of consecutive naturals, for example, 40001 + ... + 2060000.

Almost surely, 2^{2121001010000} is an apocalyptic number.

2121001010000 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 2121001010000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2593000569522).

2121001010000 is an abundant number, since it is smaller than the sum of its proper divisors (3065000129044).

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

2121001010000 is a wasteful number, since it uses less digits than its factorization.

2121001010000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100130 (or 2100109 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 2121001010000 its reverse (101001212), we get a palindrome (2121102011212).

The spelling of 2121001010000 in words is "two trillion, one hundred twenty-one billion, one million, ten thousand".