161813982 has 64 divisors (see below), whose sum is σ = 363170304. Its totient is φ = 47648640.

The previous prime is 161813963. The next prime is 161814011. The reversal of 161813982 is 289318161.

It is a self number, because there is not a number n which added to its sum of digits gives 161813982.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 584028 + ... + 584304.

It is an arithmetic number, because the mean of its divisors is an integer number (5674536).

Almost surely, 2^161813982 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161813982, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (181585152).

161813982 is an abundant number, since it is smaller than the sum of its proper divisors (201356322).

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

161813982 is a wasteful number, since it uses less digits than its factorization.

161813982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513.

The product of its digits is 20736, while the sum is 39.

The square root of 161813982 is about 12720.6124852540. The cubic root of 161813982 is about 544.9274453817.

The spelling of 161813982 in words is "one hundred sixty-one million, eight hundred thirteen thousand, nine hundred eighty-two".