21100011121 has 8 divisors (see below), whose sum is σ = 24123618944. Its totient is φ = 18078733440.

The previous prime is 21100011071. The next prime is 21100011143. The reversal of 21100011121 is 12111000112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21100011121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100011098 and 21100011107.

It is not an unprimeable number, because it can be changed into a prime (21100011161) 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, 563085 + ... + 599386.

It is an arithmetic number, because the mean of its divisors is an integer number (3015452368).

Almost surely, 2^21100011121 is an apocalyptic number.

It is an amenable number.

21100011121 is a deficient number, since it is larger than the sum of its proper divisors (3023607823).

21100011121 is a wasteful number, since it uses less digits than its factorization.

21100011121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1165071.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21100011121 its reverse (12111000112), we get a palindrome (33211011233).

The spelling of 21100011121 in words is "twenty-one billion, one hundred million, eleven thousand, one hundred twenty-one".