263478979 has 4 divisors (see below), whose sum is σ = 264275320. Its totient is φ = 262682640.

The previous prime is 263478959. The next prime is 263478989. The reversal of 263478979 is 979874362.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-263478979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (263478959) 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 in 3 ways as a sum of consecutive naturals, for example, 397674 + ... + 398335.

It is an arithmetic number, because the mean of its divisors is an integer number (66068830).

Almost surely, 2^263478979 is an apocalyptic number.

263478979 is a deficient number, since it is larger than the sum of its proper divisors (796341).

263478979 is an equidigital number, since it uses as much as digits as its factorization.

263478979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 796340.

The product of its digits is 4572288, while the sum is 55.

The square root of 263478979 is about 16232.0355778319. The cubic root of 263478979 is about 641.0845696978.

The spelling of 263478979 in words is "two hundred sixty-three million, four hundred seventy-eight thousand, nine hundred seventy-nine".