5505555561 has 16 divisors (see below), whose sum is σ = 8033845248. Its totient is φ = 3325965200.

The previous prime is 5505555541. The next prime is 5505555593. The reversal of 5505555561 is 1655555055.

It is a cyclic number.

It is not a de Polignac number, because 5505555561 - 2⁵ = 5505555529 is a prime.

It is a super-4 number, since 4×5505555561⁴ (a number of 40 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (5505555521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 257961 + ... + 278486.

It is an arithmetic number, because the mean of its divisors is an integer number (502115328).

Almost surely, 2^5505555561 is an apocalyptic number.

It is an amenable number.

5505555561 is a deficient number, since it is larger than the sum of its proper divisors (2528289687).

5505555561 is a wasteful number, since it uses less digits than its factorization.

5505555561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536772.

The product of its (nonzero) digits is 468750, while the sum is 42.

The square root of 5505555561 is about 74199.4310018615. The cubic root of 5505555561 is about 1765.7683029812.

It can be divided in two parts, 550 and 5555561, that added together give a triangular number (5556111 = T₃₃₃₃).

The spelling of 5505555561 in words is "five billion, five hundred five million, five hundred fifty-five thousand, five hundred sixty-one".