221211120065 has 16 divisors (see below), whose sum is σ = 287059046736. Its totient is φ = 162678067200.

The previous prime is 221211120029. The next prime is 221211120083. The reversal of 221211120065 is 560021112122.

It can be written as a sum of positive squares in 8 ways, for example, as 1103767729 + 220107352336 = 33223^2 + 469156^2 .

It is not a de Polignac number, because 221211120065 - 2²⁴ = 221194342849 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221211120065.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7045016 + ... + 7076345.

It is an arithmetic number, because the mean of its divisors is an integer number (17941190421).

Almost surely, 2^221211120065 is an apocalyptic number.

It is an amenable number.

221211120065 is a deficient number, since it is larger than the sum of its proper divisors (65847926671).

221211120065 is a wasteful number, since it uses less digits than its factorization.

221211120065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14121620.

The product of its (nonzero) digits is 480, while the sum is 23.

Adding to 221211120065 its reverse (560021112122), we get a palindrome (781232232187).

The spelling of 221211120065 in words is "two hundred twenty-one billion, two hundred eleven million, one hundred twenty thousand, sixty-five".