66605305 has 8 divisors (see below), whose sum is σ = 86074632. Its totient is φ = 49185408.

The previous prime is 66605299. The next prime is 66605311. The reversal of 66605305 is 50350666.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66605299) and next prime (66605311).

It can be written as a sum of positive squares in 4 ways, for example, as 1915456 + 64689849 = 1384^2 + 8043^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66605305 - 2¹⁵ = 66572537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 512284 + ... + 512413.

It is an arithmetic number, because the mean of its divisors is an integer number (10759329).

Almost surely, 2^66605305 is an apocalyptic number.

66605305 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66605305 is a deficient number, since it is larger than the sum of its proper divisors (19469327).

66605305 is a wasteful number, since it uses less digits than its factorization.

66605305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1024715.

The product of its (nonzero) digits is 16200, while the sum is 31.

The square root of 66605305 is about 8161.2073248999. The cubic root of 66605305 is about 405.3556901665.

The spelling of 66605305 in words is "sixty-six million, six hundred five thousand, three hundred five".