263640563 has 2 divisors, whose sum is σ = 263640564. Its totient is φ = 263640562.

The previous prime is 263640557. The next prime is 263640571. The reversal of 263640563 is 365046362.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 263640563 - 2⁶ = 263640499 is a prime.

It is not a weakly prime, because it can be changed into another prime (263645563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131820281 + 131820282.

It is an arithmetic number, because the mean of its divisors is an integer number (131820282).

Almost surely, 2^263640563 is an apocalyptic number.

263640563 is a deficient number, since it is larger than the sum of its proper divisors (1).

263640563 is an equidigital number, since it uses as much as digits as its factorization.

263640563 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 35.

The square root of 263640563 is about 16237.0121327786. The cubic root of 263640563 is about 641.2155957613.

The spelling of 263640563 in words is "two hundred sixty-three million, six hundred forty thousand, five hundred sixty-three".