166765306613 has 4 divisors (see below), whose sum is σ = 171272477100. Its totient is φ = 162258136128.

The previous prime is 166765306531. The next prime is 166765306621. The reversal of 166765306613 is 316603567661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 80748042244 + 86017264369 = 284162^2 + 293287^2 .

It is a cyclic number.

It is not a de Polignac number, because 166765306613 - 2¹⁶ = 166765241077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166765306663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2253585188 + ... + 2253585261.

It is an arithmetic number, because the mean of its divisors is an integer number (42818119275).

Almost surely, 2^166765306613 is an apocalyptic number.

It is an amenable number.

166765306613 is a deficient number, since it is larger than the sum of its proper divisors (4507170487).

166765306613 is an equidigital number, since it uses as much as digits as its factorization.

166765306613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4507170486.

The product of its (nonzero) digits is 2449440, while the sum is 50.

The spelling of 166765306613 in words is "one hundred sixty-six billion, seven hundred sixty-five million, three hundred six thousand, six hundred thirteen".