23565963509 has 24 divisors (see below), whose sum is σ = 26879219136. Its totient is φ = 20630332800.

The previous prime is 23565963479. The next prime is 23565963517. The reversal of 23565963509 is 90536956532.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-23565963509 is a prime.

It is a super-2 number, since 2×23565963509² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23565963529) 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 23 ways as a sum of consecutive naturals, for example, 337517 + ... + 401309.

It is an arithmetic number, because the mean of its divisors is an integer number (1119967464).

Almost surely, 2^23565963509 is an apocalyptic number.

It is an amenable number.

23565963509 is a deficient number, since it is larger than the sum of its proper divisors (3313255627).

23565963509 is a wasteful number, since it uses less digits than its factorization.

23565963509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63929 (or 63918 counting only the distinct ones).

The product of its (nonzero) digits is 6561000, while the sum is 53.

The spelling of 23565963509 in words is "twenty-three billion, five hundred sixty-five million, nine hundred sixty-three thousand, five hundred nine".