161980 has 48 divisors (see below), whose sum is σ = 423360. Its totient is φ = 50688.

The previous prime is 161977. The next prime is 161983. The reversal of 161980 is 89161.

It is an interprime number because it is at equal distance from previous prime (161977) and next prime (161983).

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161983) 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, 1776 + ... + 1864.

It is an arithmetic number, because the mean of its divisors is an integer number (8820).

2¹⁶¹⁹⁸⁰ is an apocalyptic number.

161980 is a gapful number since it is divisible by the number (10) 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 161980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211680).

161980 is an abundant number, since it is smaller than the sum of its proper divisors (261380).

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

161980 is a wasteful number, since it uses less digits than its factorization.

161980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 116 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 161980 is about 402.4673899833. The cubic root of 161980 is about 54.5113743339.

The spelling of 161980 in words is "one hundred sixty-one thousand, nine hundred eighty".