666011816 has 8 divisors (see below), whose sum is σ = 1248772170. Its totient is φ = 333005904.

The previous prime is 666011789. The next prime is 666011849. The reversal of 666011816 is 618110666.

It can be written as a sum of positive squares in only one way, i.e., 499343716 + 166668100 = 22346^2 + 12910^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41625731 + ... + 41625746.

Almost surely, 2^666011816 is an apocalyptic number.

It is an amenable number.

666011816 is a deficient number, since it is larger than the sum of its proper divisors (582760354).

666011816 is a wasteful number, since it uses less digits than its factorization.

666011816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83251483 (or 83251479 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 666011816 is about 25807.2047304624. The cubic root of 666011816 is about 873.2943386561.

The spelling of 666011816 in words is "six hundred sixty-six million, eleven thousand, eight hundred sixteen".