21021210020101 has 4 divisors (see below), whose sum is σ = 21022092139104. Its totient is φ = 21020327901100.

The previous prime is 21021210020089. The next prime is 21021210020123. The reversal of 21021210020101 is 10102001212012.

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 a de Polignac number, because none of the positive numbers 2^k-21021210020101 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 (21021210020141) 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, 441023755 + ... + 441071416.

It is an arithmetic number, because the mean of its divisors is an integer number (5255523034776).

Almost surely, 2^{21021210020101} is an apocalyptic number.

It is an amenable number.

21021210020101 is a deficient number, since it is larger than the sum of its proper divisors (882119003).

21021210020101 is an equidigital number, since it uses as much as digits as its factorization.

21021210020101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 882119002.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21021210020101 its reverse (10102001212012), we get a palindrome (31123211232113).

The spelling of 21021210020101 in words is "twenty-one trillion, twenty-one billion, two hundred ten million, twenty thousand, one hundred one".