161784 has 64 divisors (see below), whose sum is σ = 518400. Its totient is φ = 45792.

The previous prime is 161783. The next prime is 161807. The reversal of 161784 is 487161.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1459 + ... + 1565.

It is an arithmetic number, because the mean of its divisors is an integer number (8100).

2¹⁶¹⁷⁸⁴ is an apocalyptic number.

161784 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (259200).

161784 is an abundant number, since it is smaller than the sum of its proper divisors (356616).

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

161784 is a wasteful number, since it uses less digits than its factorization.

161784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 119 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 161784 is about 402.2238182903. The cubic root of 161784 is about 54.4893787343.

The spelling of 161784 in words is "one hundred sixty-one thousand, seven hundred eighty-four".