21002110212101 has 16 divisors (see below), whose sum is σ = 22144415214960. Its totient is φ = 19887960368640.

The previous prime is 21002110212067. The next prime is 21002110212179. The reversal of 21002110212101 is 10121201120012.

It can be written as a sum of positive squares in 8 ways, for example, as 2163046732900 + 18839063479201 = 1470730^2 + 4340399^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002110212101 - 2²² = 21002106017797 is a prime.

It is a super-2 number, since 2×21002110212101² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002110212001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1651571 + ... + 6688191.

It is an arithmetic number, because the mean of its divisors is an integer number (1384025950935).

Almost surely, 2^{21002110212101} is an apocalyptic number.

It is an amenable number.

21002110212101 is a deficient number, since it is larger than the sum of its proper divisors (1142305002859).

21002110212101 is a wasteful number, since it uses less digits than its factorization.

21002110212101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5039416.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21002110212101 its reverse (10121201120012), we get a palindrome (31123311332113).

The spelling of 21002110212101 in words is "twenty-one trillion, two billion, one hundred ten million, two hundred twelve thousand, one hundred one".