21102110210121 has 16 divisors (see below), whose sum is σ = 28928750178048. Its totient is φ = 13674304137600.

The previous prime is 21102110210113. The next prime is 21102110210123. The reversal of 21102110210121 is 12101201120112.

It is a happy number.

It is not a de Polignac number, because 21102110210121 - 2³ = 21102110210113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21102110210121.

It is not an unprimeable number, because it can be changed into a prime (21102110210123) 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, 316501486 + ... + 316568151.

It is an arithmetic number, because the mean of its divisors is an integer number (1808046886128).

Almost surely, 2^{21102110210121} is an apocalyptic number.

It is an amenable number.

21102110210121 is a deficient number, since it is larger than the sum of its proper divisors (7826639967927).

21102110210121 is a wasteful number, since it uses less digits than its factorization.

21102110210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633069952.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21102110210121 its reverse (12101201120112), we get a palindrome (33203311330233).

Subtracting from 21102110210121 its reverse (12101201120112), we obtain a palindrome (9000909090009).

The spelling of 21102110210121 in words is "twenty-one trillion, one hundred two billion, one hundred ten million, two hundred ten thousand, one hundred twenty-one".