263947993 has 2 divisors, whose sum is σ = 263947994. Its totient is φ = 263947992.

The previous prime is 263947991. The next prime is 263948017. The reversal of 263947993 is 399749362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 169702729 + 94245264 = 13027^2 + 9708^2 .

It is a cyclic number.

It is not a de Polignac number, because 263947993 - 2¹ = 263947991 is a prime.

Together with 263947991, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 263947993.

It is not a weakly prime, because it can be changed into another prime (263947991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131973996 + 131973997.

It is an arithmetic number, because the mean of its divisors is an integer number (131973997).

Almost surely, 2^263947993 is an apocalyptic number.

It is an amenable number.

263947993 is a deficient number, since it is larger than the sum of its proper divisors (1).

263947993 is an equidigital number, since it uses as much as digits as its factorization.

263947993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2204496, while the sum is 52.

The square root of 263947993 is about 16246.4763256529. The cubic root of 263947993 is about 641.4647384252.

The spelling of 263947993 in words is "two hundred sixty-three million, nine hundred forty-seven thousand, nine hundred ninety-three".