21213611546121 has 48 divisors (see below), whose sum is σ = 33647363568000. Its totient is φ = 13309957801728.

The previous prime is 21213611546111. The next prime is 21213611546137. The reversal of 21213611546121 is 12164511631212.

21213611546121 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 36 + 1 + 1 + 5 + 4 + 612 + 1 = 666.

It is not a de Polignac number, because 21213611546121 - 2⁷ = 21213611545993 is a prime.

It is a super-2 number, since 2×21213611546121² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21213611546111) 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 47 ways as a sum of consecutive naturals, for example, 116853780 + ... + 117035178.

It is an arithmetic number, because the mean of its divisors is an integer number (700986741000).

Almost surely, 2^{21213611546121} is an apocalyptic number.

It is an amenable number.

21213611546121 is a deficient number, since it is larger than the sum of its proper divisors (12433752021879).

21213611546121 is a wasteful number, since it uses less digits than its factorization.

21213611546121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209740 (or 209728 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The spelling of 21213611546121 in words is "twenty-one trillion, two hundred thirteen billion, six hundred eleven million, five hundred forty-six thousand, one hundred twenty-one".