21102220122100 has 36 divisors (see below), whose sum is σ = 49314265180684. Its totient is φ = 7791588967680.

The previous prime is 21102220122059. The next prime is 21102220122103. The reversal of 21102220122100 is 122102220112.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 6736469776 + 21095483652324 = 82076^2 + 4592982^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102220122103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8116237209 + ... + 8116239808.

Almost surely, 2^{21102220122100} is an apocalyptic number.

21102220122100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21102220122100 is an abundant number, since it is smaller than the sum of its proper divisors (28212045058584).

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

21102220122100 is a wasteful number, since it uses less digits than its factorization.

21102220122100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16232477044 (or 16232477037 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21102220122100 its reverse (122102220112), we get a palindrome (21224322342212).

The spelling of 21102220122100 in words is "twenty-one trillion, one hundred two billion, two hundred twenty million, one hundred twenty-two thousand, one hundred".