2121121200 has 480 divisors, whose sum is σ = 7866853632. Its totient is φ = 483840000.

The previous prime is 2121121199. The next prime is 2121121201. The reversal of 2121121200 is 21211212.

It is an interprime number because it is at equal distance from previous prime (2121121199) and next prime (2121121201).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (2121121201) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 21001150 + ... + 21001250.

Almost surely, 2^2121121200 is an apocalyptic number.

2121121200 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 2121121200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3933426816).

2121121200 is an abundant number, since it is smaller than the sum of its proper divisors (5745732432).

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

2121121200 is a wasteful number, since it uses less digits than its factorization.

2121121200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213 (or 202 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 2121121200 is about 46055.6315774738. The cubic root of 2121121200 is about 1284.8580846267.

Adding to 2121121200 its reverse (21211212), we get a palindrome (2142332412).

2121121200 divided by its reverse (21211212) gives a square (100 = 10²).

It can be divided in two parts, 212112 and 1200, that added together give a palindrome (213312).

The spelling of 2121121200 in words is "two billion, one hundred twenty-one million, one hundred twenty-one thousand, two hundred".