161917056 has 320 divisors, whose sum is σ = 580567680. Its totient is φ = 43794432.

The previous prime is 161917043. The next prime is 161917081. The reversal of 161917056 is 650719161.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 161917056.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1669200 + ... + 1669296.

It is an arithmetic number, because the mean of its divisors is an integer number (1814274).

Almost surely, 2^161917056 is an apocalyptic number.

161917056 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 161917056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (290283840).

161917056 is an abundant number, since it is smaller than the sum of its proper divisors (418650624).

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

161917056 is an equidigital number, since it uses as much as digits as its factorization.

161917056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 36.

The square root of 161917056 is about 12724.6632961348. The cubic root of 161917056 is about 545.0431253925.

The spelling of 161917056 in words is "one hundred sixty-one million, nine hundred seventeen thousand, fifty-six".