21020101101 has 40 divisors (see below), whose sum is σ = 31759526304. Its totient is φ = 13853682720.

The previous prime is 21020101099. The next prime is 21020101127. The reversal of 21020101101 is 10110102012.

It is a happy number.

It is not a de Polignac number, because 21020101101 - 2¹ = 21020101099 is a prime.

It is a super-2 number, since 2×21020101101² (a number of 21 digits) contains 22 as substring.

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 (21020101301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4686606 + ... + 4691088.

Almost surely, 2^21020101101 is an apocalyptic number.

It is an amenable number.

21020101101 is a deficient number, since it is larger than the sum of its proper divisors (10739425203).

21020101101 is a wasteful number, since it uses less digits than its factorization.

21020101101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5143 (or 5134 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21020101101 its reverse (10110102012), we get a palindrome (31130203113).

The spelling of 21020101101 in words is "twenty-one billion, twenty million, one hundred one thousand, one hundred one".