161723856 has 160 divisors (see below), whose sum is σ = 527966208. Its totient is φ = 41564160.

The previous prime is 161723843. The next prime is 161723911. The reversal of 161723856 is 658327161.

161723856 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 130761 + ... + 131991.

Almost surely, 2^161723856 is an apocalyptic number.

161723856 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 161723856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263983104).

161723856 is an abundant number, since it is smaller than the sum of its proper divisors (366242352).

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

161723856 is a wasteful number, since it uses less digits than its factorization.

161723856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1289 (or 1283 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The square root of 161723856 is about 12717.0694737428. The cubic root of 161723856 is about 544.8262566562.

The spelling of 161723856 in words is "one hundred sixty-one million, seven hundred twenty-three thousand, eight hundred fifty-six".