21100011121121 has 4 divisors (see below), whose sum is σ = 21113476349952. Its totient is φ = 21086545892292.

The previous prime is 21100011121103. The next prime is 21100011121127. The reversal of 21100011121121 is 12112111000112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21100011121121 - 2⁴² = 16701964610017 is a prime.

It is a super-2 number, since 2×21100011121121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100011121096 and 21100011121105.

It is not an unprimeable number, because it can be changed into a prime (21100011121127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6732612065 + ... + 6732615198.

It is an arithmetic number, because the mean of its divisors is an integer number (5278369087488).

Almost surely, 2^{21100011121121} is an apocalyptic number.

It is an amenable number.

21100011121121 is a deficient number, since it is larger than the sum of its proper divisors (13465228831).

21100011121121 is a wasteful number, since it uses less digits than its factorization.

21100011121121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13465228830.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21100011121121 its reverse (12112111000112), we get a palindrome (33212122121233).

The spelling of 21100011121121 in words is "twenty-one trillion, one hundred billion, eleven million, one hundred twenty-one thousand, one hundred twenty-one".