21216330100 has 72 divisors (see below), whose sum is σ = 52677753408. Its totient is φ = 7265702400.

The previous prime is 21216330097. The next prime is 21216330101. The reversal of 21216330100 is 103361212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216330101) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 599499 + ... + 633901.

It is an arithmetic number, because the mean of its divisors is an integer number (731635464).

Almost surely, 2^21216330100 is an apocalyptic number.

21216330100 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 21216330100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26338876704).

21216330100 is an abundant number, since it is smaller than the sum of its proper divisors (31461423308).

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

21216330100 is a wasteful number, since it uses less digits than its factorization.

21216330100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35305 (or 35298 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21216330100 its reverse (103361212), we get a palindrome (21319691312).

The spelling of 21216330100 in words is "twenty-one billion, two hundred sixteen million, three hundred thirty thousand, one hundred".