5661056615491 has 4 divisors (see below), whose sum is σ = 5994059945832. Its totient is φ = 5328053285152.

The previous prime is 5661056615449. The next prime is 5661056615509. The reversal of 5661056615491 is 1945166501665.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5661056615491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5661050615491) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166501665145 + ... + 166501665178.

It is an arithmetic number, because the mean of its divisors is an integer number (1498514986458).

Almost surely, 2^{5661056615491} is an apocalyptic number.

5661056615491 is a deficient number, since it is larger than the sum of its proper divisors (333003330341).

5661056615491 is a wasteful number, since it uses less digits than its factorization.

5661056615491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333003330340.

The product of its (nonzero) digits is 5832000, while the sum is 55.

The spelling of 5661056615491 in words is "five trillion, six hundred sixty-one billion, fifty-six million, six hundred fifteen thousand, four hundred ninety-one".