18385517033 has 4 divisors (see below), whose sum is σ = 19799787588. Its totient is φ = 16971246480.

The previous prime is 18385516997. The next prime is 18385517093. The reversal of 18385517033 is 33071558381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 33071558381 = 6343 ⋅5213867.

It can be written as a sum of positive squares in 2 ways, for example, as 8666120464 + 9719396569 = 93092^2 + 98587^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18385517033 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18385517093) 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, 707135258 + ... + 707135283.

It is an arithmetic number, because the mean of its divisors is an integer number (4949946897).

Almost surely, 2^18385517033 is an apocalyptic number.

18385517033 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

18385517033 is a deficient number, since it is larger than the sum of its proper divisors (1414270555).

18385517033 is a wasteful number, since it uses less digits than its factorization.

18385517033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1414270554.

The product of its (nonzero) digits is 302400, while the sum is 44.

The spelling of 18385517033 in words is "eighteen billion, three hundred eighty-five million, five hundred seventeen thousand, thirty-three".