21121211100013 has 16 divisors (see below), whose sum is σ = 21975128326144. Its totient is φ = 20278094014080.

The previous prime is 21121211100007. The next prime is 21121211100061. The reversal of 21121211100013 is 31000111212112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21121211100013 - 2²⁹ = 21120674229101 is a prime.

It is a super-2 number, since 2×21121211100013² (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 21121211100013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121211100713) 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, 107764081 + ... + 107959897.

It is an arithmetic number, because the mean of its divisors is an integer number (1373445520384).

Almost surely, 2^{21121211100013} is an apocalyptic number.

It is an amenable number.

21121211100013 is a deficient number, since it is larger than the sum of its proper divisors (853917226131).

21121211100013 is a wasteful number, since it uses less digits than its factorization.

21121211100013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223372.

The product of its (nonzero) digits is 24, while the sum is 16.

Adding to 21121211100013 its reverse (31000111212112), we get a palindrome (52121322312125).

The spelling of 21121211100013 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, one hundred thousand, thirteen".