16855321181 has 4 divisors (see below), whose sum is σ = 16869104352. Its totient is φ = 16841538012.

The previous prime is 16855321163. The next prime is 16855321183. The reversal of 16855321181 is 18112355861.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18112355861 = 14321 ⋅1264741.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16855321181 is a prime.

It is a super-2 number, since 2×16855321181² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16855321183) 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, 6889751 + ... + 6892196.

It is an arithmetic number, because the mean of its divisors is an integer number (4217276088).

Almost surely, 2^16855321181 is an apocalyptic number.

It is an amenable number.

16855321181 is a deficient number, since it is larger than the sum of its proper divisors (13783171).

16855321181 is a wasteful number, since it uses less digits than its factorization.

16855321181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13783170.

The product of its digits is 57600, while the sum is 41.

The spelling of 16855321181 in words is "sixteen billion, eight hundred fifty-five million, three hundred twenty-one thousand, one hundred eighty-one".