21220102121 has 24 divisors (see below), whose sum is σ = 22089038400. Its totient is φ = 20382516000.

The previous prime is 21220102097. The next prime is 21220102129. The reversal of 21220102121 is 12120102212.

It is a de Polignac number, because none of the positive numbers 2^k-21220102121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21220102096 and 21220102105.

It is not an unprimeable number, because it can be changed into a prime (21220102129) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 37162766 + ... + 37163336.

It is an arithmetic number, because the mean of its divisors is an integer number (920376600).

Almost surely, 2^21220102121 is an apocalyptic number.

It is an amenable number.

21220102121 is a deficient number, since it is larger than the sum of its proper divisors (868936279).

21220102121 is a wasteful number, since it uses less digits than its factorization.

21220102121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 957 (or 914 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21220102121 its reverse (12120102212), we get a palindrome (33340204333).

Subtracting from 21220102121 its reverse (12120102212), we obtain a palindrome (9099999909).

The spelling of 21220102121 in words is "twenty-one billion, two hundred twenty million, one hundred two thousand, one hundred twenty-one".