263661317 has 4 divisors (see below), whose sum is σ = 263694540. Its totient is φ = 263628096.

The previous prime is 263661257. The next prime is 263661323. The reversal of 263661317 is 713166362.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 51638596 + 212022721 = 7186^2 + 14561^2 .

It is a cyclic number.

It is not a de Polignac number, because 263661317 - 2¹² = 263657221 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 (263660317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3053 + ... + 23165.

It is an arithmetic number, because the mean of its divisors is an integer number (65923635).

Almost surely, 2^263661317 is an apocalyptic number.

It is an amenable number.

263661317 is a deficient number, since it is larger than the sum of its proper divisors (33223).

263661317 is a wasteful number, since it uses less digits than its factorization.

263661317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33222.

The product of its digits is 27216, while the sum is 35.

The square root of 263661317 is about 16237.6512156161. The cubic root of 263661317 is about 641.2324209912.

The spelling of 263661317 in words is "two hundred sixty-three million, six hundred sixty-one thousand, three hundred seventeen".