166981459 has 4 divisors (see below), whose sum is σ = 170534304. Its totient is φ = 163428616.

The previous prime is 166981453. The next prime is 166981483. The reversal of 166981459 is 954189661.

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

It is a cyclic number.

It is not a de Polignac number, because 166981459 - 2²⁵ = 133427027 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166981453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1776352 + ... + 1776445.

It is an arithmetic number, because the mean of its divisors is an integer number (42633576).

Almost surely, 2^166981459 is an apocalyptic number.

166981459 is a deficient number, since it is larger than the sum of its proper divisors (3552845).

166981459 is an equidigital number, since it uses as much as digits as its factorization.

166981459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3552844.

The product of its digits is 466560, while the sum is 49.

The square root of 166981459 is about 12922.1305905799. The cubic root of 166981459 is about 550.6674640375.

The spelling of 166981459 in words is "one hundred sixty-six million, nine hundred eighty-one thousand, four hundred fifty-nine".