166257643 has 4 divisors (see below), whose sum is σ = 166294648. Its totient is φ = 166220640.

The previous prime is 166257617. The next prime is 166257653. The reversal of 166257643 is 346752661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 346752661 = 523 ⋅663007.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166257643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166257596 and 166257605.

It is not an unprimeable number, because it can be changed into a prime (166257653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10653 + ... + 21118.

It is an arithmetic number, because the mean of its divisors is an integer number (41573662).

Almost surely, 2^166257643 is an apocalyptic number.

166257643 is a deficient number, since it is larger than the sum of its proper divisors (37005).

166257643 is an equidigital number, since it uses as much as digits as its factorization.

166257643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37004.

The product of its digits is 181440, while the sum is 40.

The square root of 166257643 is about 12894.0933376488. The cubic root of 166257643 is about 549.8706505736.

The spelling of 166257643 in words is "one hundred sixty-six million, two hundred fifty-seven thousand, six hundred forty-three".