166220513 has 2 divisors, whose sum is σ = 166220514. Its totient is φ = 166220512.

The previous prime is 166220491. The next prime is 166220533. The reversal of 166220513 is 315022661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 143448529 + 22771984 = 11977^2 + 4772^2 .

It is a cyclic number.

It is not a de Polignac number, because 166220513 - 2¹² = 166216417 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (166220533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83110256 + 83110257.

It is an arithmetic number, because the mean of its divisors is an integer number (83110257).

Almost surely, 2^166220513 is an apocalyptic number.

It is an amenable number.

166220513 is a deficient number, since it is larger than the sum of its proper divisors (1).

166220513 is an equidigital number, since it uses as much as digits as its factorization.

166220513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 166220513 is about 12892.6534507059. The cubic root of 166220513 is about 549.8297136740.

The spelling of 166220513 in words is "one hundred sixty-six million, two hundred twenty thousand, five hundred thirteen".