161128220 has 48 divisors (see below), whose sum is σ = 377008128. Its totient is φ = 57341760.

The previous prime is 161128211. The next prime is 161128223. The reversal of 161128220 is 22821161.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161128223) 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, 2549 + ... + 18131.

It is an arithmetic number, because the mean of its divisors is an integer number (7854336).

Almost surely, 2^161128220 is an apocalyptic number.

161128220 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 161128220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188504064).

161128220 is an abundant number, since it is smaller than the sum of its proper divisors (215879908).

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

161128220 is a wasteful number, since it uses less digits than its factorization.

161128220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15650 (or 15648 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 161128220 is about 12693.6291106996. The cubic root of 161128220 is about 544.1565608709.

Adding to 161128220 its reverse (22821161), we get a palindrome (183949381).

The spelling of 161128220 in words is "one hundred sixty-one million, one hundred twenty-eight thousand, two hundred twenty".