2121000000000 has 800 divisors, whose sum is σ = 8152030415232. Its totient is φ = 480000000000.

The previous prime is 2120999999941. The next prime is 2121000000017. The reversal of 2121000000000 is 1212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (800).

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 20999999950 + ... + 21000000050.

Almost surely, 2^{2121000000000} is an apocalyptic number.

2121000000000 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 2121000000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4076015207616).

2121000000000 is an abundant number, since it is smaller than the sum of its proper divisors (6031030415232).

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

2121000000000 is an frugal number, since it uses more digits than its factorization.

2121000000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

Adding to 2121000000000 its reverse (1212), we get a palindrome (2121000001212).

The spelling of 2121000000000 in words is "two trillion, one hundred twenty-one billion", and thus it is an aban number.