21001110010101 has 64 divisors (see below), whose sum is σ = 35538754944000. Its totient is φ = 12150099299520.

The previous prime is 21001110010061. The next prime is 21001110010123. The reversal of 21001110010101 is 10101001110012.

It is not a de Polignac number, because 21001110010101 - 2⁶ = 21001110010037 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 (21001110010151) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11145691 + ... + 12892968.

It is an arithmetic number, because the mean of its divisors is an integer number (555293046000).

Almost surely, 2^{21001110010101} is an apocalyptic number.

It is an amenable number.

21001110010101 is a deficient number, since it is larger than the sum of its proper divisors (14537644933899).

21001110010101 is a wasteful number, since it uses less digits than its factorization.

21001110010101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24038831 (or 24038825 counting only the distinct ones).

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

Adding to 21001110010101 its reverse (10101001110012), we get a palindrome (31102111120113).

The spelling of 21001110010101 in words is "twenty-one trillion, one billion, one hundred ten million, ten thousand, one hundred one".