5561666 has 16 divisors (see below), whose sum is σ = 9194688. Its totient is φ = 2502000.

The previous prime is 5561659. The next prime is 5561687. The reversal of 5561666 is 6661655.

5561666 = T₅₆₄ + T₅₆₅ + ... + T₅₉₆.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 971 + ... + 3473.

It is an arithmetic number, because the mean of its divisors is an integer number (574668).

Almost surely, 2^5561666 is an apocalyptic number.

5561666 is a deficient number, since it is larger than the sum of its proper divisors (3633022).

5561666 is a wasteful number, since it uses less digits than its factorization.

5561666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2617.

The product of its digits is 32400, while the sum is 35.

The square root of 5561666 is about 2358.3184687400. The cubic root of 5561666 is about 177.1746709002.

It can be divided in two parts, 556 and 1666, that added together give a palindrome (2222).

The spelling of 5561666 in words is "five million, five hundred sixty-one thousand, six hundred sixty-six".