166820072 has 8 divisors (see below), whose sum is σ = 312787650. Its totient is φ = 83410032.

The previous prime is 166820063. The next prime is 166820077. The reversal of 166820072 is 270028661.

It can be written as a sum of positive squares in only one way, i.e., 160934596 + 5885476 = 12686^2 + 2426^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (166820077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10426247 + ... + 10426262.

Almost surely, 2^166820072 is an apocalyptic number.

It is an amenable number.

166820072 is a deficient number, since it is larger than the sum of its proper divisors (145967578).

166820072 is a wasteful number, since it uses less digits than its factorization.

166820072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20852515 (or 20852511 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 166820072 is about 12915.8844838439. The cubic root of 166820072 is about 550.4900007891.

The spelling of 166820072 in words is "one hundred sixty-six million, eight hundred twenty thousand, seventy-two".