21220321313100 has 432 divisors, whose sum is σ = 77477025715488. Its totient is φ = 4444568432640.

The previous prime is 21220321313071. The next prime is 21220321313111. The reversal of 21220321313100 is 131312302212.

It is a super-2 number, since 2×21220321313100² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 25775434 + ... + 26585966.

It is an arithmetic number, because the mean of its divisors is an integer number (179344966934).

Almost surely, 2^{21220321313100} is an apocalyptic number.

21220321313100 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 21220321313100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38738512857744).

21220321313100 is an abundant number, since it is smaller than the sum of its proper divisors (56256704402388).

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

21220321313100 is a wasteful number, since it uses less digits than its factorization.

21220321313100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810714 (or 810700 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 21220321313100 its reverse (131312302212), we get a palindrome (21351633615312).

The spelling of 21220321313100 in words is "twenty-one trillion, two hundred twenty billion, three hundred twenty-one million, three hundred thirteen thousand, one hundred".