21120102111221 has 16 divisors (see below), whose sum is σ = 22379792578560. Its totient is φ = 19903649650560.

The previous prime is 21120102111181. The next prime is 21120102111247. The reversal of 21120102111221 is 12211120102112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120102111221 is a prime.

It is a super-2 number, since 2×21120102111221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21120102111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120102101221) 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, 58889510 + ... + 59247063.

It is an arithmetic number, because the mean of its divisors is an integer number (1398737036160).

Almost surely, 2^{21120102111221} is an apocalyptic number.

It is an amenable number.

21120102111221 is a deficient number, since it is larger than the sum of its proper divisors (1259690467339).

21120102111221 is a wasteful number, since it uses less digits than its factorization.

21120102111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118136756.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21120102111221 its reverse (12211120102112), we get a palindrome (33331222213333).

The spelling of 21120102111221 in words is "twenty-one trillion, one hundred twenty billion, one hundred two million, one hundred eleven thousand, two hundred twenty-one".