161907856 has 120 divisors (see below), whose sum is σ = 375225984. Its totient is φ = 67034880.

The previous prime is 161907839. The next prime is 161907871. The reversal of 161907856 is 658709161.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3444825 + ... + 3444871.

Almost surely, 2^161907856 is an apocalyptic number.

161907856 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 161907856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187612992).

161907856 is an abundant number, since it is smaller than the sum of its proper divisors (213318128).

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

161907856 is a wasteful number, since it uses less digits than its factorization.

161907856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 161907856 is about 12724.3017883104. The cubic root of 161907856 is about 545.0328022229.

The spelling of 161907856 in words is "one hundred sixty-one million, nine hundred seven thousand, eight hundred fifty-six".