21012000121221 has 8 divisors (see below), whose sum is σ = 28016748462144. Its totient is φ = 14007625930560.

The previous prime is 21012000121181. The next prime is 21012000121271. The reversal of 21012000121221 is 12212100021012.

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

It is not a de Polignac number, because 21012000121221 - 2¹⁰ = 21012000120197 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21012000121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012000121271) 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, 93406500 + ... + 93631181.

It is an arithmetic number, because the mean of its divisors is an integer number (3502093557768).

Almost surely, 2^{21012000121221} is an apocalyptic number.

It is an amenable number.

21012000121221 is a deficient number, since it is larger than the sum of its proper divisors (7004748340923).

21012000121221 is a wasteful number, since it uses less digits than its factorization.

21012000121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187075131.

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

Adding to 21012000121221 its reverse (12212100021012), we get a palindrome (33224100142233).

The spelling of 21012000121221 in words is "twenty-one trillion, twelve billion, one hundred twenty-one thousand, two hundred twenty-one".