181573851641 has 18 divisors (see below), whose sum is σ = 228715968222. Its totient is φ = 143662821120.

The previous prime is 181573851611. The next prime is 181573851761. The reversal of 181573851641 is 146158375181.

181573851641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 7097220025 + 174476631616 = 84245^2 + 417704^2 .

It is not a de Polignac number, because 181573851641 - 2¹⁰ = 181573850617 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 181573851641.

It is not an unprimeable number, because it can be changed into a prime (181573851611) 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 17 ways as a sum of consecutive naturals, for example, 10955000 + ... + 10971561.

It is an arithmetic number, because the mean of its divisors is an integer number (12706442679).

Almost surely, 2^181573851641 is an apocalyptic number.

It is an amenable number.

181573851641 is a deficient number, since it is larger than the sum of its proper divisors (47142116581).

181573851641 is a wasteful number, since it uses less digits than its factorization.

181573851641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21926601 (or 21926581 counting only the distinct ones).

The product of its digits is 806400, while the sum is 50.

The spelling of 181573851641 in words is "one hundred eighty-one billion, five hundred seventy-three million, eight hundred fifty-one thousand, six hundred forty-one".