21100010020101 has 6 divisors (see below), whose sum is σ = 30477792251270. Its totient is φ = 14066673346728.

The previous prime is 21100010020091. The next prime is 21100010020123. The reversal of 21100010020101 is 10102001000112.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16663295484900 + 4436714535201 = 4082070^2 + 2106351^2 .

It is not a de Polignac number, because 21100010020101 - 2¹¹ = 21100010018053 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: 2344445557789 = 21100010020101 / (2 + 1 + 1 + 0 + 0 + 0 + 1 + 0 + 0 + 2 + 0 + 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 (21100010020181) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1172222778886 + ... + 1172222778903.

Almost surely, 2^{21100010020101} is an apocalyptic number.

It is an amenable number.

21100010020101 is a deficient number, since it is larger than the sum of its proper divisors (9377782231169).

21100010020101 is a wasteful number, since it uses less digits than its factorization.

21100010020101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2344445557795 (or 2344445557792 counting only the distinct ones).

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

Adding to 21100010020101 its reverse (10102001000112), we get a palindrome (31202011020213).

The spelling of 21100010020101 in words is "twenty-one trillion, one hundred billion, ten million, twenty thousand, one hundred one".