221041304042221 has 6 divisors (see below), whose sum is σ = 239352417986730. Its totient is φ = 204038126808048.

The previous prime is 221041304042191. The next prime is 221041304042227. The reversal of 221041304042221 is 122240403140122.

It can be written as a sum of positive squares in 3 ways, for example, as 2248542236196 + 218792761806025 = 1499514^2 + 14791645^2 .

It is not a de Polignac number, because 221041304042221 - 2³⁵ = 221006944303853 is a prime.

It is a super-2 number, since 2×221041304042221² (a number of 29 digits) contains 22 as substring.

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 221041304042221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221041304042227) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 653968354986 + ... + 653968355323.

It is an arithmetic number, because the mean of its divisors is an integer number (39892069664455).

Almost surely, 2^{221041304042221} is an apocalyptic number.

It is an amenable number.

221041304042221 is a deficient number, since it is larger than the sum of its proper divisors (18311113944509).

221041304042221 is a wasteful number, since it uses less digits than its factorization.

221041304042221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1307936710335 (or 1307936710322 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 28.

Adding to 221041304042221 its reverse (122240403140122), we get a palindrome (343281707182343).

The spelling of 221041304042221 in words is "two hundred twenty-one trillion, forty-one billion, three hundred four million, forty-two thousand, two hundred twenty-one".