550645666 has 4 divisors (see below), whose sum is σ = 825968502. Its totient is φ = 275322832.

The previous prime is 550645663. The next prime is 550645681. The reversal of 550645666 is 666546055.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 473715225 + 76930441 = 21765^2 + 8771^2 .

It is not an unprimeable number, because it can be changed into a prime (550645661) by changing a digit.

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, 137661415 + ... + 137661418.

Almost surely, 2^550645666 is an apocalyptic number.

550645666 is a deficient number, since it is larger than the sum of its proper divisors (275322836).

550645666 is a wasteful number, since it uses less digits than its factorization.

550645666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275322835.

The product of its (nonzero) digits is 648000, while the sum is 43.

The square root of 550645666 is about 23465.8404068552. The cubic root of 550645666 is about 819.6417560642.

The spelling of 550645666 in words is "five hundred fifty million, six hundred forty-five thousand, six hundred sixty-six".