166612261 has 2 divisors, whose sum is σ = 166612262. Its totient is φ = 166612260.

The previous prime is 166612249. The next prime is 166612307. The reversal of 166612261 is 162216661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 140541025 + 26071236 = 11855^2 + 5106^2 .

It is a cyclic number.

It is not a de Polignac number, because 166612261 - 2⁹ = 166611749 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166612241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83306130 + 83306131.

It is an arithmetic number, because the mean of its divisors is an integer number (83306131).

Almost surely, 2^166612261 is an apocalyptic number.

It is an amenable number.

166612261 is a deficient number, since it is larger than the sum of its proper divisors (1).

166612261 is an equidigital number, since it uses as much as digits as its factorization.

166612261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 31.

The square root of 166612261 is about 12907.8371929615. The cubic root of 166612261 is about 550.2613204478.

The spelling of 166612261 in words is "one hundred sixty-six million, six hundred twelve thousand, two hundred sixty-one".