21000101000101 has 4 divisors (see below), whose sum is σ = 21000744990304. Its totient is φ = 20999457009900.

The previous prime is 21000101000077. The next prime is 21000101000149. The reversal of 21000101000101 is 10100010100012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21000101000101 - 2⁵ = 21000101000069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000101000701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321946185 + ... + 322011406.

It is an arithmetic number, because the mean of its divisors is an integer number (5250186247576).

Almost surely, 2^{21000101000101} is an apocalyptic number.

It is an amenable number.

21000101000101 is a deficient number, since it is larger than the sum of its proper divisors (643990203).

21000101000101 is an equidigital number, since it uses as much as digits as its factorization.

21000101000101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643990202.

The product of its (nonzero) digits is 2, while the sum is 7.

Adding to 21000101000101 its reverse (10100010100012), we get a palindrome (31100111100113).

The spelling of 21000101000101 in words is "twenty-one trillion, one hundred one million, one hundred one", and thus it is an aban number.