21116021206065 has 32 divisors (see below), whose sum is σ = 34610131180800. Its totient is φ = 10987052820480.

The previous prime is 21116021206019. The next prime is 21116021206069. The reversal of 21116021206065 is 56060212061112.

It is not a de Polignac number, because 21116021206065 - 2⁶ = 21116021206001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21116021206069) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 58835881 + ... + 59193689.

It is an arithmetic number, because the mean of its divisors is an integer number (1081566599400).

Almost surely, 2^{21116021206065} is an apocalyptic number.

It is an amenable number.

21116021206065 is a deficient number, since it is larger than the sum of its proper divisors (13494109974735).

21116021206065 is a wasteful number, since it uses less digits than its factorization.

21116021206065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453817.

The product of its (nonzero) digits is 8640, while the sum is 33.

Adding to 21116021206065 its reverse (56060212061112), we get a palindrome (77176233267177).

The spelling of 21116021206065 in words is "twenty-one trillion, one hundred sixteen billion, twenty-one million, two hundred six thousand, sixty-five".