21102000001221 has 8 divisors (see below), whose sum is σ = 28137608670304. Its totient is φ = 14067195666480.

The previous prime is 21102000001213. The next prime is 21102000001273. The reversal of 21102000001221 is 12210000020112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21102000001221 - 2³ = 21102000001213 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21102000001197 and 21102000001206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102000001721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 201022366 + ... + 201127311.

It is an arithmetic number, because the mean of its divisors is an integer number (3517201083788).

Almost surely, 2^{21102000001221} is an apocalyptic number.

It is an amenable number.

21102000001221 is a deficient number, since it is larger than the sum of its proper divisors (7035608669083).

21102000001221 is a wasteful number, since it uses less digits than its factorization.

21102000001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402167171.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21102000001221 its reverse (12210000020112), we get a palindrome (33312000021333).

The spelling of 21102000001221 in words is "twenty-one trillion, one hundred two billion, one thousand, two hundred twenty-one".