556661605 has 4 divisors (see below), whose sum is σ = 667993932. Its totient is φ = 445329280.

The previous prime is 556661603. The next prime is 556661653. The reversal of 556661605 is 506166655.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 506166655 = 5 ⋅101233331.

It can be written as a sum of positive squares in 2 ways, for example, as 262504804 + 294156801 = 16202^2 + 17151^2 .

It is not a de Polignac number, because 556661605 - 2¹ = 556661603 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (556661603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55666156 + ... + 55666165.

It is an arithmetic number, because the mean of its divisors is an integer number (166998483).

Almost surely, 2^556661605 is an apocalyptic number.

It is an amenable number.

556661605 is a deficient number, since it is larger than the sum of its proper divisors (111332327).

556661605 is a wasteful number, since it uses less digits than its factorization.

556661605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111332326.

The product of its (nonzero) digits is 162000, while the sum is 40.

The square root of 556661605 is about 23593.6772250533. The cubic root of 556661605 is about 822.6158802988.

The spelling of 556661605 in words is "five hundred fifty-six million, six hundred sixty-one thousand, six hundred five".