166906565765 has 16 divisors (see below), whose sum is σ = 203641666032. Its totient is φ = 131306932224.

The previous prime is 166906565747. The next prime is 166906565789. The reversal of 166906565765 is 567565609661.

It is a happy number.

It is a Cunningham number, because it is equal to 408542²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 1 + 166906565764 = 1^2 + 408542^2 .

It is a cyclic number.

It is not a de Polignac number, because 166906565765 - 2¹⁸ = 166906303621 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166906565698 and 166906565707.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1019834 + ... + 1172123.

It is an arithmetic number, because the mean of its divisors is an integer number (12727604127).

Almost surely, 2^166906565765 is an apocalyptic number.

It is an amenable number.

166906565765 is a deficient number, since it is larger than the sum of its proper divisors (36735100267).

166906565765 is a wasteful number, since it uses less digits than its factorization.

166906565765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2192216.

The product of its (nonzero) digits is 61236000, while the sum is 62.

The spelling of 166906565765 in words is "one hundred sixty-six billion, nine hundred six million, five hundred sixty-five thousand, seven hundred sixty-five".