21120656054121 has 16 divisors (see below), whose sum is σ = 33696773192320. Its totient is φ = 12997326802320.

The previous prime is 21120656054063. The next prime is 21120656054137. The reversal of 21120656054121 is 12145065602112.

21120656054121 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 0 + 6 + 5 + 605 + 41 + 2 + 1 = 666.

It is not a de Polignac number, because 21120656054121 - 2¹⁹ = 21120655529833 is a prime.

It is a super-2 number, since 2×21120656054121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21120656050121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30086404285 + ... + 30086404986.

It is an arithmetic number, because the mean of its divisors is an integer number (2106048324520).

Almost surely, 2^{21120656054121} is an apocalyptic number.

It is an amenable number.

21120656054121 is a deficient number, since it is larger than the sum of its proper divisors (12576117138199).

21120656054121 is a wasteful number, since it uses less digits than its factorization.

21120656054121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60172809293 (or 60172809287 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 21120656054121 in words is "twenty-one trillion, one hundred twenty billion, six hundred fifty-six million, fifty-four thousand, one hundred twenty-one".