20181535823 has 4 divisors (see below), whose sum is σ = 20377473168. Its totient is φ = 19985598480.

The previous prime is 20181535819. The next prime is 20181535853. The reversal of 20181535823 is 32853518102.

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 20181535823 - 2² = 20181535819 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 (20181535853) 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, 97968518 + ... + 97968723.

It is an arithmetic number, because the mean of its divisors is an integer number (5094368292).

Almost surely, 2^20181535823 is an apocalyptic number.

20181535823 is a deficient number, since it is larger than the sum of its proper divisors (195937345).

20181535823 is a wasteful number, since it uses less digits than its factorization.

20181535823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195937344.

The product of its (nonzero) digits is 57600, while the sum is 38.

The spelling of 20181535823 in words is "twenty billion, one hundred eighty-one million, five hundred thirty-five thousand, eight hundred twenty-three".