172057166261 has 2 divisors, whose sum is σ = 172057166262. Its totient is φ = 172057166260.

The previous prime is 172057166249. The next prime is 172057166293. The reversal of 172057166261 is 162661750271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 133147631236 + 38909535025 = 364894^2 + 197255^2 .

It is an emirp because it is prime and its reverse (162661750271) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172057166261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172057166461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86028583130 + 86028583131.

It is an arithmetic number, because the mean of its divisors is an integer number (86028583131).

Almost surely, 2^172057166261 is an apocalyptic number.

It is an amenable number.

172057166261 is a deficient number, since it is larger than the sum of its proper divisors (1).

172057166261 is an equidigital number, since it uses as much as digits as its factorization.

172057166261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 211680, while the sum is 44.

The spelling of 172057166261 in words is "one hundred seventy-two billion, fifty-seven million, one hundred sixty-six thousand, two hundred sixty-one".