21100002220 has 24 divisors (see below), whose sum is σ = 48338187408. Its totient is φ = 7672728000.

The previous prime is 21100002181. The next prime is 21100002221. The reversal of 21100002220 is 2220000112.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 21100002197 and 21100002206.

It is not an unprimeable number, because it can be changed into a prime (21100002221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47954331 + ... + 47954770.

It is an arithmetic number, because the mean of its divisors is an integer number (2014091142).

Almost surely, 2^21100002220 is an apocalyptic number.

21100002220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100002220 is an abundant number, since it is smaller than the sum of its proper divisors (27238185188).

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

21100002220 is a wasteful number, since it uses less digits than its factorization.

21100002220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95909121 (or 95909119 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21100002220 its reverse (2220000112), we get a palindrome (23320002332).

The spelling of 21100002220 in words is "twenty-one billion, one hundred million, two thousand, two hundred twenty".