161443240 has 120 divisors (see below), whose sum is σ = 434351070. Its totient is φ = 54001920.

The previous prime is 161443229. The next prime is 161443277. The reversal of 161443240 is 42344161.

It can be written as a sum of positive squares in 3 ways, for example, as 43112356 + 118330884 = 6566^2 + 10878^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3937620 + ... + 3937660.

Almost surely, 2^161443240 is an apocalyptic number.

161443240 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 161443240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217175535).

161443240 is an abundant number, since it is smaller than the sum of its proper divisors (272907830).

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

161443240 is an frugal number, since it uses more digits than its factorization.

161443240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 55 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 161443240 is about 12706.0316385565. The cubic root of 161443240 is about 544.5109548376.

The spelling of 161443240 in words is "one hundred sixty-one million, four hundred forty-three thousand, two hundred forty".