21215043304 has 128 divisors (see below), whose sum is σ = 49511105280. Its totient is φ = 8298547200.

The previous prime is 21215043277. The next prime is 21215043341. The reversal of 21215043304 is 40334051212.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30701599 + ... + 30702289.

It is an arithmetic number, because the mean of its divisors is an integer number (386805510).

Almost surely, 2^21215043304 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 21215043304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24755552640).

21215043304 is an abundant number, since it is smaller than the sum of its proper divisors (28296061976).

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

21215043304 is a wasteful number, since it uses less digits than its factorization.

21215043304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1131 (or 1127 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

Adding to 21215043304 its reverse (40334051212), we get a palindrome (61549094516).

The spelling of 21215043304 in words is "twenty-one billion, two hundred fifteen million, forty-three thousand, three hundred four".