1665798047 has 2 divisors, whose sum is σ = 1665798048. Its totient is φ = 1665798046.

The previous prime is 1665798031. The next prime is 1665798073. The reversal of 1665798047 is 7408975661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1665798047 - 2⁴ = 1665798031 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1665798047.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665798347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832899023 + 832899024.

It is an arithmetic number, because the mean of its divisors is an integer number (832899024).

Almost surely, 2^1665798047 is an apocalyptic number.

1665798047 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665798047 is an equidigital number, since it uses as much as digits as its factorization.

1665798047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2540160, while the sum is 53.

The square root of 1665798047 is about 40814.1892851003. The cubic root of 1665798047 is about 1185.4250932055.

The spelling of 1665798047 in words is "one billion, six hundred sixty-five million, seven hundred ninety-eight thousand, forty-seven".