181552251816 has 96 divisors (see below), whose sum is σ = 529886153160. Its totient is φ = 55824385536.

The previous prime is 181552251779. The next prime is 181552251847. The reversal of 181552251816 is 618152255181.

181552251816 is a `hidden beast` number, since 1 + 81 + 5 + 52 + 2 + 518 + 1 + 6 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 168748424100 + 12803827716 = 410790^2 + 113154^2 .

It is a super-2 number, since 2×181552251816² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1332490 + ... + 1462406.

Almost surely, 2^181552251816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181552251816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264943076580).

181552251816 is an abundant number, since it is smaller than the sum of its proper divisors (348333901344).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

181552251816 is a wasteful number, since it uses less digits than its factorization.

181552251816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131435 (or 131428 counting only the distinct ones).

The product of its digits is 192000, while the sum is 45.

The spelling of 181552251816 in words is "one hundred eighty-one billion, five hundred fifty-two million, two hundred fifty-one thousand, eight hundred sixteen".