11555603666 has 8 divisors (see below), whose sum is σ = 17334211980. Its totient is φ = 5777533008.

The previous prime is 11555603659. The next prime is 11555603671. The reversal of 11555603666 is 66630655511.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 11263364641 + 292239025 = 106129^2 + 17095^2 .

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

It is a Curzon number.

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 in 3 ways as a sum of consecutive naturals, for example, 75521 + ... + 169748.

Almost surely, 2^11555603666 is an apocalyptic number.

11555603666 is a deficient number, since it is larger than the sum of its proper divisors (5778608314).

11555603666 is a wasteful number, since it uses less digits than its factorization.

11555603666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268828.

The product of its (nonzero) digits is 486000, while the sum is 44.

The spelling of 11555603666 in words is "eleven billion, five hundred fifty-five million, six hundred three thousand, six hundred sixty-six".