263238643 has 4 divisors (see below), whose sum is σ = 264853768. Its totient is φ = 261623520.

The previous prime is 263238637. The next prime is 263238649. The reversal of 263238643 is 346832362.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 346832362 = 2 ⋅173416181.

It is an interprime number because it is at equal distance from previous prime (263238637) and next prime (263238649).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-263238643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (263238649) 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, 807318 + ... + 807643.

It is an arithmetic number, because the mean of its divisors is an integer number (66213442).

Almost surely, 2^263238643 is an apocalyptic number.

263238643 is a deficient number, since it is larger than the sum of its proper divisors (1615125).

263238643 is a wasteful number, since it uses less digits than its factorization.

263238643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1615124.

The product of its digits is 124416, while the sum is 37.

The square root of 263238643 is about 16224.6307508060. The cubic root of 263238643 is about 640.8895856768.

The spelling of 263238643 in words is "two hundred sixty-three million, two hundred thirty-eight thousand, six hundred forty-three".