221131111111177 has 2 divisors, whose sum is σ = 221131111111178. Its totient is φ = 221131111111176.

The previous prime is 221131111111139. The next prime is 221131111111201. The reversal of 221131111111177 is 771111111131122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155982015004176 + 65149096107001 = 12489276^2 + 8071499^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221131111111177 is a prime.

It is not a weakly prime, because it can be changed into another prime (221131111141177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110565555555588 + 110565555555589.

It is an arithmetic number, because the mean of its divisors is an integer number (110565555555589).

Almost surely, 2^{221131111111177} is an apocalyptic number.

It is an amenable number.

221131111111177 is a deficient number, since it is larger than the sum of its proper divisors (1).

221131111111177 is an equidigital number, since it uses as much as digits as its factorization.

221131111111177 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 588, while the sum is 31.

Adding to 221131111111177 its reverse (771111111131122), we get a palindrome (992242222242299).

The spelling of 221131111111177 in words is "two hundred twenty-one trillion, one hundred thirty-one billion, one hundred eleven million, one hundred eleven thousand, one hundred seventy-seven".