21120001210221 has 16 divisors (see below), whose sum is σ = 28241575689600. Its totient is φ = 14039218856960.

The previous prime is 21120001210181. The next prime is 21120001210247. The reversal of 21120001210221 is 12201210002112.

It is a cyclic number.

It is not a de Polignac number, because 21120001210221 - 2¹³ = 21120001202029 is a prime.

It is a super-2 number, since 2×21120001210221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21120001210221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120001210261) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16190080 + ... + 17445878.

It is an arithmetic number, because the mean of its divisors is an integer number (1765098480600).

Almost surely, 2^{21120001210221} is an apocalyptic number.

It is an amenable number.

21120001210221 is a deficient number, since it is larger than the sum of its proper divisors (7121574479379).

21120001210221 is a wasteful number, since it uses less digits than its factorization.

21120001210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1272036.

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

Adding to 21120001210221 its reverse (12201210002112), we get a palindrome (33321211212333).

The spelling of 21120001210221 in words is "twenty-one trillion, one hundred twenty billion, one million, two hundred ten thousand, two hundred twenty-one".