161906400 has 216 divisors, whose sum is σ = 578869200. Its totient is φ = 42577920.

The previous prime is 161906389. The next prime is 161906411. The reversal of 161906400 is 4609161.

161906400 is a `hidden beast` number, since 1 + 6 + 19 + 0 + 640 + 0 = 666.

161906400 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (161906389) and next prime (161906411).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 813501 + ... + 813699.

It is an arithmetic number, because the mean of its divisors is an integer number (2679950).

Almost surely, 2^161906400 is an apocalyptic number.

161906400 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 161906400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289434600).

161906400 is an abundant number, since it is smaller than the sum of its proper divisors (416962800).

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

161906400 is a wasteful number, since it uses less digits than its factorization.

161906400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338 (or 322 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 161906400 is about 12724.2445748264. The cubic root of 161906400 is about 545.0311684332.

The spelling of 161906400 in words is "one hundred sixty-one million, nine hundred six thousand, four hundred".