2101122121221 has 16 divisors (see below), whose sum is σ = 3112827013120. Its totient is φ = 1400724005760.

The previous prime is 2101122121193. The next prime is 2101122121247. The reversal of 2101122121221 is 1221212211012.

2101122121221 is a `hidden beast` number, since 210 + 1 + 1 + 221 + 212 + 21 = 666.

It is not a de Polignac number, because 2101122121221 - 2¹⁰ = 2101122120197 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2101122121194 and 2101122121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101122131221) 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, 1007676 + ... + 2284218.

It is an arithmetic number, because the mean of its divisors is an integer number (194551688320).

Almost surely, 2^{2101122121221} is an apocalyptic number.

It is an amenable number.

2101122121221 is a deficient number, since it is larger than the sum of its proper divisors (1011704891899).

2101122121221 is a wasteful number, since it uses less digits than its factorization.

2101122121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1337513 (or 1337507 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 2101122121221 its reverse (1221212211012), we get a palindrome (3322334332233).

The spelling of 2101122121221 in words is "two trillion, one hundred one billion, one hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty-one".