172211342221 has 2 divisors, whose sum is σ = 172211342222. Its totient is φ = 172211342220.

The previous prime is 172211342179. The next prime is 172211342323. The reversal of 172211342221 is 122243112271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 144693508996 + 27517833225 = 380386^2 + 165885^2 .

It is a cyclic number.

It is not a de Polignac number, because 172211342221 - 2¹⁵ = 172211309453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 172211342221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172211346221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86105671110 + 86105671111.

It is an arithmetic number, because the mean of its divisors is an integer number (86105671111).

Almost surely, 2^172211342221 is an apocalyptic number.

It is an amenable number.

172211342221 is a deficient number, since it is larger than the sum of its proper divisors (1).

172211342221 is an equidigital number, since it uses as much as digits as its factorization.

172211342221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2688, while the sum is 28.

Adding to 172211342221 its reverse (122243112271), we get a palindrome (294454454492).

The spelling of 172211342221 in words is "one hundred seventy-two billion, two hundred eleven million, three hundred forty-two thousand, two hundred twenty-one".