5561661016505 has 16 divisors (see below), whose sum is σ = 7281665610624. Its totient is φ = 4044318967680.

The previous prime is 5561661016481. The next prime is 5561661016531. The reversal of 5561661016505 is 5056101661655.

It is not a de Polignac number, because 5561661016505 - 2³⁴ = 5544481147321 is a prime.

It is a super-2 number, since 2×5561661016505² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 5561661016505.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6140084 + ... + 6987413.

It is an arithmetic number, because the mean of its divisors is an integer number (455104100664).

Almost surely, 2^{5561661016505} is an apocalyptic number.

5561661016505 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

5561661016505 is a deficient number, since it is larger than the sum of its proper divisors (1720004594119).

5561661016505 is a wasteful number, since it uses less digits than its factorization.

5561661016505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13135216.

The product of its (nonzero) digits is 810000, while the sum is 47.

The spelling of 5561661016505 in words is "five trillion, five hundred sixty-one billion, six hundred sixty-one million, sixteen thousand, five hundred five".