18685416653 has 4 divisors (see below), whose sum is σ = 18718963740. Its totient is φ = 18651869568.

The previous prime is 18685416613. The next prime is 18685416671. The reversal of 18685416653 is 35661458681.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35661458681 = 84991 ⋅419591.

It can be written as a sum of positive squares in 2 ways, for example, as 8085066889 + 10600349764 = 89917^2 + 102958^2 .

It is a cyclic number.

It is not a de Polignac number, because 18685416653 - 2³⁴ = 1505547469 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18685416595 and 18685416604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18685416613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16772708 + ... + 16773821.

It is an arithmetic number, because the mean of its divisors is an integer number (4679740935).

Almost surely, 2^18685416653 is an apocalyptic number.

It is an amenable number.

18685416653 is a deficient number, since it is larger than the sum of its proper divisors (33547087).

18685416653 is an equidigital number, since it uses as much as digits as its factorization.

18685416653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33547086.

The product of its digits is 4147200, while the sum is 53.

The spelling of 18685416653 in words is "eighteen billion, six hundred eighty-five million, four hundred sixteen thousand, six hundred fifty-three".