166481978 has 8 divisors (see below), whose sum is σ = 268932468. Its totient is φ = 76837824.

The previous prime is 166481977. The next prime is 166481983. The reversal of 166481978 is 879184661.

It can be written as a sum of positive squares in 2 ways, for example, as 162996289 + 3485689 = 12767^2 + 1867^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166481977) 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 in 3 ways as a sum of consecutive naturals, for example, 3201551 + ... + 3201602.

Almost surely, 2^166481978 is an apocalyptic number.

166481978 is a deficient number, since it is larger than the sum of its proper divisors (102450490).

166481978 is a wasteful number, since it uses less digits than its factorization.

166481978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6403168.

The product of its digits is 580608, while the sum is 50.

The square root of 166481978 is about 12902.7895433507. The cubic root of 166481978 is about 550.1178568369.

The spelling of 166481978 in words is "one hundred sixty-six million, four hundred eighty-one thousand, nine hundred seventy-eight".