161786844 has 18 divisors (see below), whose sum is σ = 408961280. Its totient is φ = 53928936.

The previous prime is 161786839. The next prime is 161786857. The reversal of 161786844 is 448687161.

It is a tau number, because it is divible by the number of its divisors (18).

It is a self number, because there is not a number n which added to its sum of digits gives 161786844.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2247004 + ... + 2247075.

Almost surely, 2^161786844 is an apocalyptic number.

It is an amenable number.

161786844 is an abundant number, since it is smaller than the sum of its proper divisors (247174436).

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

161786844 is a wasteful number, since it uses less digits than its factorization.

161786844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4494089 (or 4494084 counting only the distinct ones).

The product of its digits is 258048, while the sum is 45.

The square root of 161786844 is about 12719.5457466059. The cubic root of 161786844 is about 544.8969802191.

The spelling of 161786844 in words is "one hundred sixty-one million, seven hundred eighty-six thousand, eight hundred forty-four".