2121335456 has 48 divisors (see below), whose sum is σ = 4317401088. Its totient is φ = 1024953600.

The previous prime is 2121335453. The next prime is 2121335473. The reversal of 2121335456 is 6545331212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (2121335453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1003841 + ... + 1005951.

It is an arithmetic number, because the mean of its divisors is an integer number (89945856).

Almost surely, 2^2121335456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2121335456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2158700544).

2121335456 is an abundant number, since it is smaller than the sum of its proper divisors (2196065632).

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

2121335456 is a wasteful number, since it uses less digits than its factorization.

2121335456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3165 (or 3157 counting only the distinct ones).

The product of its digits is 21600, while the sum is 32.

The square root of 2121335456 is about 46057.9575752117. The cubic root of 2121335456 is about 1284.9013446544.

Adding to 2121335456 its reverse (6545331212), we get a palindrome (8666666668).

The spelling of 2121335456 in words is "two billion, one hundred twenty-one million, three hundred thirty-five thousand, four hundred fifty-six".