23281787539 has 4 divisors (see below), whose sum is σ = 23459511240. Its totient is φ = 23104063840.

The previous prime is 23281787533. The next prime is 23281787561. The reversal of 23281787539 is 93578718232.

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

It is a cyclic number.

It is not a de Polignac number, because 23281787539 - 2⁷ = 23281787411 is a prime.

It is a super-2 number, since 2×23281787539² (a number of 22 digits) contains 22 as substring.

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 23281787539.

It is not an unprimeable number, because it can be changed into a prime (23281787533) 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, 88861654 + ... + 88861915.

It is an arithmetic number, because the mean of its divisors is an integer number (5864877810).

Almost surely, 2^23281787539 is an apocalyptic number.

23281787539 is a deficient number, since it is larger than the sum of its proper divisors (177723701).

23281787539 is a wasteful number, since it uses less digits than its factorization.

23281787539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177723700.

The product of its digits is 5080320, while the sum is 55.

It can be divided in two parts, 232817 and 87539, that added together give a square (320356 = 566²).

The spelling of 23281787539 in words is "twenty-three billion, two hundred eighty-one million, seven hundred eighty-seven thousand, five hundred thirty-nine".