2121404500 has 144 divisors (see below), whose sum is σ = 5032682928. Its totient is φ = 780748800.

The previous prime is 2121404489. The next prime is 2121404521. The reversal of 2121404500 is 54041212.

It can be written as a sum of positive squares in 24 ways, for example, as 1782697284 + 338707216 = 42222^2 + 18404^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7658362 + ... + 7658638.

It is an arithmetic number, because the mean of its divisors is an integer number (34949187).

Almost surely, 2^2121404500 is an apocalyptic number.

2121404500 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 2121404500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2516341464).

2121404500 is an abundant number, since it is smaller than the sum of its proper divisors (2911278428).

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

2121404500 is a wasteful number, since it uses less digits than its factorization.

2121404500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383 (or 354 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 2121404500 is about 46058.7071030006. The cubic root of 2121404500 is about 1284.9152845785.

Adding to 2121404500 its reverse (54041212), we get a palindrome (2175445712).

The spelling of 2121404500 in words is "two billion, one hundred twenty-one million, four hundred four thousand, five hundred".