181684985 has 12 divisors (see below), whose sum is σ = 224140644. Its totient is φ = 141276960.

The previous prime is 181684969. The next prime is 181684991. The reversal of 181684985 is 589486181.

It can be written as a sum of positive squares in 2 ways, for example, as 118831801 + 62853184 = 10901^2 + 7928^2 .

It is not a de Polignac number, because 181684985 - 2⁴ = 181684969 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 182840 + ... + 183830.

It is an arithmetic number, because the mean of its divisors is an integer number (18678387).

Almost surely, 2^181684985 is an apocalyptic number.

It is an amenable number.

181684985 is a deficient number, since it is larger than the sum of its proper divisors (42455659).

181684985 is an frugal number, since it uses more digits than its factorization.

181684985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2024 (or 1033 counting only the distinct ones).

The product of its digits is 552960, while the sum is 50.

The square root of 181684985 is about 13479.0572741568. The cubic root of 181684985 is about 566.3779611628.

The spelling of 181684985 in words is "one hundred eighty-one million, six hundred eighty-four thousand, nine hundred eighty-five".