2121000000 has 392 divisors, whose sum is σ = 8096146368. Its totient is φ = 480000000.

The previous prime is 2120999989. The next prime is 2121000023. The reversal of 2121000000 is 1212.

It is a happy number.

2121000000 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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 55 ways as a sum of consecutive naturals, for example, 20999950 + ... + 21000050.

Almost surely, 2^2121000000 is an apocalyptic number.

2121000000 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 2121000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4048073184).

2121000000 is an abundant number, since it is smaller than the sum of its proper divisors (5975146368).

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

2121000000 is an frugal number, since it uses more digits than its factorization.

2121000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153 (or 118 counting only the distinct ones).

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

The square root of 2121000000 is about 46054.3157586778. The cubic root of 2121000000 is about 1284.8336120717.

Adding to 2121000000 its reverse (1212), we get a palindrome (2121001212).

It can be divided in two parts, 21 and 21000000, that multiplied together give a square (441000000 = 21000²).

The spelling of 2121000000 in words is "two billion, one hundred twenty-one million", and thus it is an aban number.