161489538 has 56 divisors (see below), whose sum is σ = 415095168. Its totient is φ = 46136952.

The previous prime is 161489519. The next prime is 161489539. The reversal of 161489538 is 835984161.

161489538 is a `hidden beast` number, since 161 + 489 + 5 + 3 + 8 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 161489493 and 161489502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161489539) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 2295 + ... + 18117.

Almost surely, 2^161489538 is an apocalyptic number.

161489538 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 161489538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (207547584).

161489538 is an abundant number, since it is smaller than the sum of its proper divisors (253605630).

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

161489538 is an equidigital number, since it uses as much as digits as its factorization.

161489538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15850 (or 15835 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 161489538 is about 12707.8533985878. The cubic root of 161489538 is about 544.5630007016.

The spelling of 161489538 in words is "one hundred sixty-one million, four hundred eighty-nine thousand, five hundred thirty-eight".