56716891691 has 4 divisors (see below), whose sum is σ = 57678195000. Its totient is φ = 55755588384.

The previous prime is 56716891687. The next prime is 56716891703. The reversal of 56716891691 is 19619861765.

56716891691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 56716891691 - 2² = 56716891687 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (59), and also a Moran number because the ratio is a prime number: 961303249 = 56716891691 / (5 + 6 + 7 + 1 + 6 + 8 + 9 + 1 + 6 + 9 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 56716891691.

It is not an unprimeable number, because it can be changed into a prime (56716291691) 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, 480651566 + ... + 480651683.

It is an arithmetic number, because the mean of its divisors is an integer number (14419548750).

Almost surely, 2^56716891691 is an apocalyptic number.

56716891691 is a deficient number, since it is larger than the sum of its proper divisors (961303309).

56716891691 is an equidigital number, since it uses as much as digits as its factorization.

56716891691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 961303308.

The product of its digits is 4898880, while the sum is 59.

The spelling of 56716891691 in words is "fifty-six billion, seven hundred sixteen million, eight hundred ninety-one thousand, six hundred ninety-one".