165664845 has 40 divisors (see below), whose sum is σ = 300102264. Its totient is φ = 87422976.

The previous prime is 165664843. The next prime is 165664859. The reversal of 165664845 is 548466561.

165664845 = T₂₈ + T₂₉ + ... + T₉₉₇.

165664845 is a `hidden beast` number, since 1 + 6 + 566 + 4 + 84 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 40717161 + 124947684 = 6381^2 + 11178^2 .

It is not a de Polignac number, because 165664845 - 2¹ = 165664843 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 165664845.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165664841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 37177 + ... + 41393.

Almost surely, 2^165664845 is an apocalyptic number.

165664845 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165664845 is a deficient number, since it is larger than the sum of its proper divisors (134437419).

165664845 is an equidigital number, since it uses as much as digits as its factorization.

165664845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4331 (or 4322 counting only the distinct ones).

The product of its digits is 691200, while the sum is 45.

The square root of 165664845 is about 12871.0856185483. The cubic root of 165664845 is about 549.2163440096.

The spelling of 165664845 in words is "one hundred sixty-five million, six hundred sixty-four thousand, eight hundred forty-five".