665566011 has 16 divisors (see below), whose sum is σ = 1075662720. Its totient is φ = 403373160.

The previous prime is 665565983. The next prime is 665566051. The reversal of 665566011 is 110665566.

It is a de Polignac number, because none of the positive numbers 2^k-665566011 is a prime.

It is a super-2 number, since 2×665566011² = 885956229996904242, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (665566051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1120185 + ... + 1120778.

It is an arithmetic number, because the mean of its divisors is an integer number (67228920).

Almost surely, 2^665566011 is an apocalyptic number.

665566011 is a deficient number, since it is larger than the sum of its proper divisors (410096709).

665566011 is a wasteful number, since it uses less digits than its factorization.

665566011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2240983 (or 2240977 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 665566011 is about 25798.5660648029. The cubic root of 665566011 is about 873.0994442757.

The spelling of 665566011 in words is "six hundred sixty-five million, five hundred sixty-six thousand, eleven".