1774728661889 has 2 divisors, whose sum is σ = 1774728661890. Its totient is φ = 1774728661888.

The previous prime is 1774728661879. The next prime is 1774728661891. The reversal of 1774728661889 is 9881668274771.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 914318440000 + 860410221889 = 956200^2 + 927583^2 .

It is a cyclic number.

It is not a de Polignac number, because 1774728661889 - 2¹⁶ = 1774728596353 is a prime.

It is a Sophie Germain prime.

Together with 1774728661891, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1774728661819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 887364330944 + 887364330945.

It is an arithmetic number, because the mean of its divisors is an integer number (887364330945).

Almost surely, 2^{1774728661889} is an apocalyptic number.

It is an amenable number.

1774728661889 is a deficient number, since it is larger than the sum of its proper divisors (1).

1774728661889 is an equidigital number, since it uses as much as digits as its factorization.

1774728661889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 455196672, while the sum is 74.

The spelling of 1774728661889 in words is "one trillion, seven hundred seventy-four billion, seven hundred twenty-eight million, six hundred sixty-one thousand, eight hundred eighty-nine".