556551661 has 8 divisors (see below), whose sum is σ = 599279040. Its totient is φ = 514934208.

The previous prime is 556551643. The next prime is 556551683. The reversal of 556551661 is 166155655.

556551661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 556551661 - 2⁷ = 556551533 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 (556551641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 276441 + ... + 278446.

It is an arithmetic number, because the mean of its divisors is an integer number (74909880).

Almost surely, 2^556551661 is an apocalyptic number.

It is an amenable number.

556551661 is a deficient number, since it is larger than the sum of its proper divisors (42727379).

556551661 is a wasteful number, since it uses less digits than its factorization.

556551661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554963.

The product of its digits is 135000, while the sum is 40.

The square root of 556551661 is about 23591.3471637378. The cubic root of 556551661 is about 822.5617195457.

The spelling of 556551661 in words is "five hundred fifty-six million, five hundred fifty-one thousand, six hundred sixty-one".