166864707481 has 2 divisors, whose sum is σ = 166864707482. Its totient is φ = 166864707480.

The previous prime is 166864707439. The next prime is 166864707487. The reversal of 166864707481 is 184707468661.

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., 97271629456 + 69593078025 = 311884^2 + 263805^2 .

It is a cyclic number.

It is not a de Polignac number, because 166864707481 - 2¹¹ = 166864705433 is a prime.

It is a super-2 number, since 2×166864707481² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166864707487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83432353740 + 83432353741.

It is an arithmetic number, because the mean of its divisors is an integer number (83432353741).

Almost surely, 2^166864707481 is an apocalyptic number.

It is an amenable number.

166864707481 is a deficient number, since it is larger than the sum of its proper divisors (1).

166864707481 is an equidigital number, since it uses as much as digits as its factorization.

166864707481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10838016, while the sum is 58.

The spelling of 166864707481 in words is "one hundred sixty-six billion, eight hundred sixty-four million, seven hundred seven thousand, four hundred eighty-one".