166418081 has 2 divisors, whose sum is σ = 166418082. Its totient is φ = 166418080.

The previous prime is 166418069. The next prime is 166418089. The reversal of 166418081 is 180814661.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130896481 + 35521600 = 11441^2 + 5960^2 .

It is a cyclic number.

It is not a de Polignac number, because 166418081 - 2²² = 162223777 is a prime.

It is a super-2 number, since 2×166418081² = 55389955367445122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166418089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83209040 + 83209041.

It is an arithmetic number, because the mean of its divisors is an integer number (83209041).

Almost surely, 2^166418081 is an apocalyptic number.

It is an amenable number.

166418081 is a deficient number, since it is larger than the sum of its proper divisors (1).

166418081 is an equidigital number, since it uses as much as digits as its factorization.

166418081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 166418081 is about 12900.3132132518. The cubic root of 166418081 is about 550.0474680794.

The spelling of 166418081 in words is "one hundred sixty-six million, four hundred eighteen thousand, eighty-one".