21021122021121 has 96 divisors (see below), whose sum is σ = 31419379031040. Its totient is φ = 13535932032000.

The previous prime is 21021122021113. The next prime is 21021122021149. The reversal of 21021122021121 is 12112022112012.

21021122021121 is a `hidden beast` number, since 2 + 1 + 0 + 211 + 220 + 211 + 21 = 666.

It is not a de Polignac number, because 21021122021121 - 2³ = 21021122021113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021122021094 and 21021122021103.

It is not an unprimeable number, because it can be changed into a prime (21021122021021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 20588757591 + ... + 20588758611.

It is an arithmetic number, because the mean of its divisors is an integer number (327285198240).

Almost surely, 2^{21021122021121} is an apocalyptic number.

It is an amenable number.

21021122021121 is a deficient number, since it is larger than the sum of its proper divisors (10398257009919).

21021122021121 is a wasteful number, since it uses less digits than its factorization.

21021122021121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2527 (or 2524 counting only the distinct ones).

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

Adding to 21021122021121 its reverse (12112022112012), we get a palindrome (33133144133133).

The spelling of 21021122021121 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-two million, twenty-one thousand, one hundred twenty-one".