18653949571 has 4 divisors (see below), whose sum is σ = 18863544600. Its totient is φ = 18444354544.

The previous prime is 18653949557. The next prime is 18653949577. The reversal of 18653949571 is 17594935681.

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 18653949571 - 2¹¹ = 18653947523 is a prime.

It is a super-2 number, since 2×18653949571² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18653949577) 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, 104797381 + ... + 104797558.

It is an arithmetic number, because the mean of its divisors is an integer number (4715886150).

Almost surely, 2^18653949571 is an apocalyptic number.

18653949571 is a deficient number, since it is larger than the sum of its proper divisors (209595029).

18653949571 is an equidigital number, since it uses as much as digits as its factorization.

18653949571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209595028.

The product of its digits is 8164800, while the sum is 58.

The spelling of 18653949571 in words is "eighteen billion, six hundred fifty-three million, nine hundred forty-nine thousand, five hundred seventy-one".