263561663 has 16 divisors (see below), whose sum is σ = 277437600. Its totient is φ = 250145280.

The previous prime is 263561587. The next prime is 263561671. The reversal of 263561663 is 366165362.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-263561663 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 (263561563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 232883 + ... + 234011.

It is an arithmetic number, because the mean of its divisors is an integer number (17339850).

Almost surely, 2^263561663 is an apocalyptic number.

263561663 is a deficient number, since it is larger than the sum of its proper divisors (13875937).

263561663 is a wasteful number, since it uses less digits than its factorization.

263561663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322.

The product of its digits is 116640, while the sum is 38.

The square root of 263561663 is about 16234.5823167706. The cubic root of 263561663 is about 641.1516236147.

The spelling of 263561663 in words is "two hundred sixty-three million, five hundred sixty-one thousand, six hundred sixty-three".