2121009000 has 192 divisors, whose sum is σ = 7275078720. Its totient is φ = 514096000.

The previous prime is 2121008993. The next prime is 2121009001. The reversal of 2121009000 is 9001212.

It is a happy number.

2121009000 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 (15).

It is not an unprimeable number, because it can be changed into a prime (2121009001) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 360079 + ... + 365921.

It is an arithmetic number, because the mean of its divisors is an integer number (37891035).

Almost surely, 2^2121009000 is an apocalyptic number.

2121009000 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 2121009000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3637539360).

2121009000 is an abundant number, since it is smaller than the sum of its proper divisors (5154069720).

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

2121009000 is a wasteful number, since it uses less digits than its factorization.

2121009000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5889 (or 5864 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 2121009000 is about 46054.4134692865. The cubic root of 2121009000 is about 1284.8354293727.

The spelling of 2121009000 in words is "two billion, one hundred twenty-one million, nine thousand".