2121123400 has 96 divisors (see below), whose sum is σ = 5394833280. Its totient is φ = 769184000.

The previous prime is 2121123391. The next prime is 2121123413. The reversal of 2121123400 is 43211212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 947082 + ... + 949318.

It is an arithmetic number, because the mean of its divisors is an integer number (56196180).

Almost surely, 2^2121123400 is an apocalyptic number.

2121123400 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 2121123400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2697416640).

2121123400 is an abundant number, since it is smaller than the sum of its proper divisors (3273709880).

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

2121123400 is a wasteful number, since it uses less digits than its factorization.

2121123400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2695 (or 2686 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 2121123400 is about 46055.6554616260. The cubic root of 2121123400 is about 1284.8585288394.

Adding to 2121123400 its reverse (43211212), we get a palindrome (2164334612).

It can be divided in two parts, 212112 and 3400, that added together give a palindrome (215512).

The spelling of 2121123400 in words is "two billion, one hundred twenty-one million, one hundred twenty-three thousand, four hundred".