166720234 has 4 divisors (see below), whose sum is σ = 250080354. Its totient is φ = 83360116.

The previous prime is 166720219. The next prime is 166720237. The reversal of 166720234 is 432027661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 432027661 = 13 ⋅33232897.

It can be written as a sum of positive squares in only one way, i.e., 161671225 + 5049009 = 12715^2 + 2247^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 166720196 and 166720205.

It is not an unprimeable number, because it can be changed into a prime (166720237) 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 as a sum of consecutive naturals, namely, 41680057 + ... + 41680060.

Almost surely, 2^166720234 is an apocalyptic number.

166720234 is a deficient number, since it is larger than the sum of its proper divisors (83360120).

166720234 is an equidigital number, since it uses as much as digits as its factorization.

166720234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83360119.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 166720234 is about 12912.0189745833. The cubic root of 166720234 is about 550.3801603129.

Adding to 166720234 its reverse (432027661), we get a palindrome (598747895).

The spelling of 166720234 in words is "one hundred sixty-six million, seven hundred twenty thousand, two hundred thirty-four".