21100022101221 has 16 divisors (see below), whose sum is σ = 32464573999104. Its totient is φ = 11940095723184.

The previous prime is 21100022101183. The next prime is 21100022101229. The reversal of 21100022101221 is 12210122000112.

It is not a de Polignac number, because 21100022101221 - 2¹⁰ = 21100022100197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21100022101221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100022101229) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 4877487921 + ... + 4877492246.

It is an arithmetic number, because the mean of its divisors is an integer number (2029035874944).

Almost surely, 2^{21100022101221} is an apocalyptic number.

21100022101221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21100022101221 is a deficient number, since it is larger than the sum of its proper divisors (11364551897883).

21100022101221 is a wasteful number, since it uses less digits than its factorization.

21100022101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9754980280.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21100022101221 its reverse (12210122000112), we get a palindrome (33310144101333).

The spelling of 21100022101221 in words is "twenty-one trillion, one hundred billion, twenty-two million, one hundred one thousand, two hundred twenty-one".