18723729653 has 4 divisors (see below), whose sum is σ = 19180406028. Its totient is φ = 18267053280.

The previous prime is 18723729613. The next prime is 18723729697. The reversal of 18723729653 is 35692732781.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1546219684 + 17177509969 = 39322^2 + 131063^2 .

It is a cyclic number.

It is not a de Polignac number, because 18723729653 - 2¹⁸ = 18723467509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18723729595 and 18723729604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18723729613) 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, 228338126 + ... + 228338207.

It is an arithmetic number, because the mean of its divisors is an integer number (4795101507).

Almost surely, 2^18723729653 is an apocalyptic number.

It is an amenable number.

18723729653 is a deficient number, since it is larger than the sum of its proper divisors (456676375).

18723729653 is an equidigital number, since it uses as much as digits as its factorization.

18723729653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456676374.

The product of its digits is 3810240, while the sum is 53.

The spelling of 18723729653 in words is "eighteen billion, seven hundred twenty-three million, seven hundred twenty-nine thousand, six hundred fifty-three".