21120212021121 has 12 divisors (see below), whose sum is σ = 30522023253072. Its totient is φ = 14073195039576.

The previous prime is 21120212021071. The next prime is 21120212021123. The reversal of 21120212021121 is 12112021202112.

21120212021121 is a `hidden beast` number, since 211 + 202 + 1 + 20 + 211 + 21 = 666.

It is not a de Polignac number, because 21120212021121 - 2¹⁰ = 21120212020097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21120212021094 and 21120212021103.

It is not an unprimeable number, because it can be changed into a prime (21120212021123) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 578839731 + ... + 578876216.

It is an arithmetic number, because the mean of its divisors is an integer number (2543501937756).

Almost surely, 2^{21120212021121} is an apocalyptic number.

It is an amenable number.

21120212021121 is a deficient number, since it is larger than the sum of its proper divisors (9401811231951).

21120212021121 is a wasteful number, since it uses less digits than its factorization.

21120212021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1157717980 (or 1157717977 counting only the distinct ones).

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

Adding to 21120212021121 its reverse (12112021202112), we get a palindrome (33232233223233).

The spelling of 21120212021121 in words is "twenty-one trillion, one hundred twenty billion, two hundred twelve million, twenty-one thousand, one hundred twenty-one".