2121323240 has 64 divisors (see below), whose sum is σ = 5072965200. Its totient is φ = 795578368.

The previous prime is 2121323221. The next prime is 2121323287. The reversal of 2121323240 is 423231212.

It can be written as a sum of positive squares in 8 ways, for example, as 1122384004 + 998939236 = 33502^2 + 31606^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

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 15 ways as a sum of consecutive naturals, for example, 177122 + ... + 188718.

Almost surely, 2^2121323240 is an apocalyptic number.

2121323240 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 2121323240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2536482600).

2121323240 is an abundant number, since it is smaller than the sum of its proper divisors (2951641960).

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

2121323240 is a wasteful number, since it uses less digits than its factorization.

2121323240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11894 (or 11890 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 2121323240 is about 46057.8249595006. The cubic root of 2121323240 is about 1284.8988782230.

Adding to 2121323240 its reverse (423231212), we get a palindrome (2544554452).

The spelling of 2121323240 in words is "two billion, one hundred twenty-one million, three hundred twenty-three thousand, two hundred forty".