161756 has 24 divisors (see below), whose sum is σ = 332640. Its totient is φ = 67392.

The previous prime is 161753. The next prime is 161761. The reversal of 161756 is 657161.

161756 = 149² + 150² + ... + 155².

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161753) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1430 + ... + 1538.

It is an arithmetic number, because the mean of its divisors is an integer number (13860).

2¹⁶¹⁷⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161756, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166320).

161756 is an abundant number, since it is smaller than the sum of its proper divisors (170884).

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

161756 is a wasteful number, since it uses less digits than its factorization.

161756 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173 (or 171 counting only the distinct ones).

The product of its digits is 1260, while the sum is 26.

The square root of 161756 is about 402.1890102924. The cubic root of 161756 is about 54.4862350558.

The spelling of 161756 in words is "one hundred sixty-one thousand, seven hundred fifty-six".