21110101101 has 24 divisors (see below), whose sum is σ = 33158641464. Its totient is φ = 12887562240.

The previous prime is 21110101099. The next prime is 21110101123. The reversal of 21110101101 is 10110101112.

It can be written as a sum of positive squares in 4 ways, for example, as 8742437001 + 12367664100 = 93501^2 + 111210^2 .

It is not a de Polignac number, because 21110101101 - 2¹ = 21110101099 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110101301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1858860 + ... + 1870181.

It is an arithmetic number, because the mean of its divisors is an integer number (1381610061).

Almost surely, 2^21110101101 is an apocalyptic number.

It is an amenable number.

21110101101 is a deficient number, since it is larger than the sum of its proper divisors (12048540363).

21110101101 is a wasteful number, since it uses less digits than its factorization.

21110101101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3729101 (or 3729098 counting only the distinct ones).

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

Adding to 21110101101 its reverse (10110101112), we get a palindrome (31220202213).

The spelling of 21110101101 in words is "twenty-one billion, one hundred ten million, one hundred one thousand, one hundred one".