1791221257727 has 16 divisors (see below), whose sum is σ = 1958916858912. Its totient is φ = 1624340065920.

The previous prime is 1791221257711. The next prime is 1791221257733. The reversal of 1791221257727 is 7277521221971.

It is not a de Polignac number, because 1791221257727 - 2⁴ = 1791221257711 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 (1791221257757) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7304033 + ... + 7545285.

It is an arithmetic number, because the mean of its divisors is an integer number (122432303682).

Almost surely, 2^{1791221257727} is an apocalyptic number.

1791221257727 is a deficient number, since it is larger than the sum of its proper divisors (167695601185).

1791221257727 is a wasteful number, since it uses less digits than its factorization.

1791221257727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242938.

The product of its digits is 1728720, while the sum is 53.

The spelling of 1791221257727 in words is "one trillion, seven hundred ninety-one billion, two hundred twenty-one million, two hundred fifty-seven thousand, seven hundred twenty-seven".