21100122211001 has 4 divisors (see below), whose sum is σ = 21827712632100. Its totient is φ = 20372531789904.

The previous prime is 21100122210961. The next prime is 21100122211019. The reversal of 21100122211001 is 10011222100112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10458982381225 + 10641139829776 = 3234035^2 + 3262076^2 .

It is a cyclic number.

It is not a de Polignac number, because 21100122211001 - 2³⁴ = 21082942341817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21100122214001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 363795210506 + ... + 363795210563.

It is an arithmetic number, because the mean of its divisors is an integer number (5456928158025).

Almost surely, 2^{21100122211001} is an apocalyptic number.

It is an amenable number.

21100122211001 is a deficient number, since it is larger than the sum of its proper divisors (727590421099).

21100122211001 is an equidigital number, since it uses as much as digits as its factorization.

21100122211001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 727590421098.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21100122211001 its reverse (10011222100112), we get a palindrome (31111344311113).

The spelling of 21100122211001 in words is "twenty-one trillion, one hundred billion, one hundred twenty-two million, two hundred eleven thousand, one".