263423521 has 4 divisors (see below), whose sum is σ = 263540992. Its totient is φ = 263306052.

The previous prime is 263423519. The next prime is 263423539. The reversal of 263423521 is 125324362.

263423521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 263423521 - 2¹ = 263423519 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 263423521.

It is not an unprimeable number, because it can be changed into a prime (263423821) 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, 55305 + ... + 59878.

It is an arithmetic number, because the mean of its divisors is an integer number (65885248).

Almost surely, 2^263423521 is an apocalyptic number.

It is an amenable number.

263423521 is a deficient number, since it is larger than the sum of its proper divisors (117471).

263423521 is a wasteful number, since it uses less digits than its factorization.

263423521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117470.

The product of its digits is 8640, while the sum is 28.

The square root of 263423521 is about 16230.3271994128. The cubic root of 263423521 is about 641.0395872822.

Adding to 263423521 its reverse (125324362), we get a palindrome (388747883).

The spelling of 263423521 in words is "two hundred sixty-three million, four hundred twenty-three thousand, five hundred twenty-one".