18509725823 has 4 divisors (see below), whose sum is σ = 18511543128. Its totient is φ = 18507908520.

The previous prime is 18509725811. The next prime is 18509725831. The reversal of 18509725823 is 32852790581.

It is a happy number.

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 18509725823 - 2¹⁶ = 18509660287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18509725123) 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, 893288 + ... + 913773.

It is an arithmetic number, because the mean of its divisors is an integer number (4627885782).

Almost surely, 2^18509725823 is an apocalyptic number.

18509725823 is a deficient number, since it is larger than the sum of its proper divisors (1817305).

18509725823 is a wasteful number, since it uses less digits than its factorization.

18509725823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1817304.

The product of its (nonzero) digits is 1209600, while the sum is 50.

The spelling of 18509725823 in words is "eighteen billion, five hundred nine million, seven hundred twenty-five thousand, eight hundred twenty-three".