21011011101 has 6 divisors (see below), whose sum is σ = 30349238270. Its totient is φ = 14007340728.

The previous prime is 21011011079. The next prime is 21011011111. The reversal of 21011011101 is 10111011012.

It can be written as a sum of positive squares in only one way, i.e., 12600287001 + 8410724100 = 112251^2 + 91710^2 .

It is not a de Polignac number, because 21011011101 - 2⁵ = 21011011069 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 2334556789 = 21011011101 / (2 + 1 + 0 + 1 + 1 + 0 + 1 + 1 + 1 + 0 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011011111) 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 5 ways as a sum of consecutive naturals, for example, 1167278386 + ... + 1167278403.

Almost surely, 2^21011011101 is an apocalyptic number.

It is an amenable number.

21011011101 is a deficient number, since it is larger than the sum of its proper divisors (9338227169).

21011011101 is a wasteful number, since it uses less digits than its factorization.

21011011101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2334556795 (or 2334556792 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

Adding to 21011011101 its reverse (10111011012), we get a palindrome (31122022113).

The spelling of 21011011101 in words is "twenty-one billion, eleven million, eleven thousand, one hundred one".