166071217 has 4 divisors (see below), whose sum is σ = 178845940. Its totient is φ = 153296496.

The previous prime is 166071179. The next prime is 166071233. The reversal of 166071217 is 712170661.

166071217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19927296 + 146143921 = 4464^2 + 12089^2 .

It is a cyclic number.

It is not a de Polignac number, because 166071217 - 2⁷ = 166071089 is a prime.

It is a super-2 number, since 2×166071217² = 55159298231722178, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166077217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6387342 + ... + 6387367.

It is an arithmetic number, because the mean of its divisors is an integer number (44711485).

Almost surely, 2^166071217 is an apocalyptic number.

It is an amenable number.

166071217 is a deficient number, since it is larger than the sum of its proper divisors (12774723).

166071217 is a wasteful number, since it uses less digits than its factorization.

166071217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12774722.

The product of its (nonzero) digits is 3528, while the sum is 31.

The square root of 166071217 is about 12886.8621859629. The cubic root of 166071217 is about 549.6650489481.

The spelling of 166071217 in words is "one hundred sixty-six million, seventy-one thousand, two hundred seventeen".