21001101101 has 2 divisors, whose sum is σ = 21001101102. Its totient is φ = 21001101100.

The previous prime is 21001101089. The next prime is 21001101137. The reversal of 21001101101 is 10110110012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19292932201 + 1708168900 = 138899^2 + 41330^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001101101 - 2²⁶ = 20933992237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001101161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500550550 + 10500550551.

It is an arithmetic number, because the mean of its divisors is an integer number (10500550551).

Almost surely, 2^21001101101 is an apocalyptic number.

It is an amenable number.

21001101101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001101101 is an equidigital number, since it uses as much as digits as its factorization.

21001101101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2, while the sum is 8.

Adding to 21001101101 its reverse (10110110012), we get a palindrome (31111211113).

The spelling of 21001101101 in words is "twenty-one billion, one million, one hundred one thousand, one hundred one".