221321204105 has 16 divisors (see below), whose sum is σ = 272864002320. Its totient is φ = 172208120832.

The previous prime is 221321204101. The next prime is 221321204107. The reversal of 221321204105 is 501402123122.

It can be written as a sum of positive squares in 8 ways, for example, as 102684357136 + 118636846969 = 320444^2 + 344437^2 .

It is not a de Polignac number, because 221321204105 - 2² = 221321204101 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221321204101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 285677 + ... + 724053.

It is an arithmetic number, because the mean of its divisors is an integer number (17054000145).

Almost surely, 2^221321204105 is an apocalyptic number.

It is an amenable number.

221321204105 is a deficient number, since it is larger than the sum of its proper divisors (51542798215).

221321204105 is a wasteful number, since it uses less digits than its factorization.

221321204105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441148.

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 221321204105 its reverse (501402123122), we get a palindrome (722723327227).

The spelling of 221321204105 in words is "two hundred twenty-one billion, three hundred twenty-one million, two hundred four thousand, one hundred five".