1665263 has 2 divisors, whose sum is σ = 1665264. Its totient is φ = 1665262.

The previous prime is 1665247. The next prime is 1665271. The reversal of 1665263 is 3625661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1665263 - 2⁴ = 1665247 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832631 + 832632.

It is an arithmetic number, because the mean of its divisors is an integer number (832632).

2^1665263 is an apocalyptic number.

1665263 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665263 is an equidigital number, since it uses as much as digits as its factorization.

1665263 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 29.

The square root of 1665263 is about 1290.4506964623. The cubic root of 1665263 is about 118.5298161841.

It can be divided in two parts, 16652 and 63, that multiplied together give a triangular number (1049076 = T₁₄₄₈).

The spelling of 1665263 in words is "one million, six hundred sixty-five thousand, two hundred sixty-three".