66205775 has 12 divisors (see below), whose sum is σ = 84098784. Its totient is φ = 51672000.

The previous prime is 66205723. The next prime is 66205781. The reversal of 66205775 is 57750266.

It is not a de Polignac number, because 66205775 - 2¹⁰ = 66204751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31271 + ... + 33320.

It is an arithmetic number, because the mean of its divisors is an integer number (7008232).

Almost surely, 2^66205775 is an apocalyptic number.

66205775 is a deficient number, since it is larger than the sum of its proper divisors (17893009).

66205775 is a wasteful number, since it uses less digits than its factorization.

66205775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64642 (or 64637 counting only the distinct ones).

The product of its (nonzero) digits is 88200, while the sum is 38.

The square root of 66205775 is about 8136.6931243596. The cubic root of 66205775 is about 404.5435593443.

The spelling of 66205775 in words is "sixty-six million, two hundred five thousand, seven hundred seventy-five".