161988896 has 48 divisors (see below), whose sum is σ = 332148600. Its totient is φ = 77672448.

The previous prime is 161988887. The next prime is 161988901. The reversal of 161988896 is 698889161.

It can be written as a sum of positive squares in 4 ways, for example, as 152868496 + 9120400 = 12364^2 + 3020^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 160040 + ... + 161048.

Almost surely, 2^161988896 is an apocalyptic number.

161988896 is a gapful number since it is divisible by the number (16) 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 161988896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166074300).

161988896 is an abundant number, since it is smaller than the sum of its proper divisors (170159704).

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

161988896 is a wasteful number, since it uses less digits than its factorization.

161988896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1221 (or 1213 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 56.

The square root of 161988896 is about 12727.4858475663. The cubic root of 161988896 is about 545.1237224372.

The spelling of 161988896 in words is "one hundred sixty-one million, nine hundred eighty-eight thousand, eight hundred ninety-six".