21220065101 has 16 divisors (see below), whose sum is σ = 22167363840. Its totient is φ = 20294763840.

The previous prime is 21220065077. The next prime is 21220065133. The reversal of 21220065101 is 10156002212.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21220065101 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220065701) 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 15 ways as a sum of consecutive naturals, for example, 647531 + ... + 679511.

It is an arithmetic number, because the mean of its divisors is an integer number (1385460240).

Almost surely, 2^21220065101 is an apocalyptic number.

It is an amenable number.

21220065101 is a deficient number, since it is larger than the sum of its proper divisors (947298739).

21220065101 is a wasteful number, since it uses less digits than its factorization.

21220065101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32324.

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 21220065101 its reverse (10156002212), we get a palindrome (31376067313).

The spelling of 21220065101 in words is "twenty-one billion, two hundred twenty million, sixty-five thousand, one hundred one".