21212121002101 has 8 divisors (see below), whose sum is σ = 22485502753560. Its totient is φ = 19941584798208.

The previous prime is 21212121002077. The next prime is 21212121002129. The reversal of 21212121002101 is 10120012121212.

It can be written as a sum of positive squares in 4 ways, for example, as 13552345185201 + 7659775816900 = 3681351^2 + 2767630^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21212121002101 - 2²³ = 21212112613493 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 (21212121002131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 711371536 + ... + 711401353.

It is an arithmetic number, because the mean of its divisors is an integer number (2810687844195).

Almost surely, 2^{21212121002101} is an apocalyptic number.

It is an amenable number.

21212121002101 is a deficient number, since it is larger than the sum of its proper divisors (1273381751459).

21212121002101 is a wasteful number, since it uses less digits than its factorization.

21212121002101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1422773783.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21212121002101 its reverse (10120012121212), we get a palindrome (31332133123313).

The spelling of 21212121002101 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty-one million, two thousand, one hundred one".