166155665 has 48 divisors (see below), whose sum is σ = 232093008. Its totient is φ = 113467392.

The previous prime is 166155659. The next prime is 166155667. The reversal of 166155665 is 566551661.

It can be written as a sum of positive squares in 8 ways, for example, as 10804369 + 155351296 = 3287^2 + 12464^2 .

It is not a de Polignac number, because 166155665 - 2¹⁰ = 166154641 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 (166155667) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1712897 + ... + 1712993.

It is an arithmetic number, because the mean of its divisors is an integer number (4835271).

Almost surely, 2^166155665 is an apocalyptic number.

It is an amenable number.

166155665 is a deficient number, since it is larger than the sum of its proper divisors (65937343).

166155665 is a wasteful number, since it uses less digits than its factorization.

166155665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 207 counting only the distinct ones).

The product of its digits is 162000, while the sum is 41.

The square root of 166155665 is about 12890.1382847509. The cubic root of 166155665 is about 549.7582022534.

The spelling of 166155665 in words is "one hundred sixty-six million, one hundred fifty-five thousand, six hundred sixty-five".