161664 has 32 divisors (see below), whose sum is σ = 430440. Its totient is φ = 53760.

The previous prime is 161659. The next prime is 161683. The reversal of 161664 is 466161.

161664 = 130² + 131² + ... + 138².

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×161664² = 52270497792, which contains 22 as substring.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

161664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174 + ... + 594.

2¹⁶¹⁶⁶⁴ 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 161664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (215220).

161664 is an abundant number, since it is smaller than the sum of its proper divisors (268776).

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

161664 is an equidigital number, since it uses as much as digits as its factorization.

161664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438 (or 426 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The square root of 161664 is about 402.0746199401. The cubic root of 161664 is about 54.4759032716.

The spelling of 161664 in words is "one hundred sixty-one thousand, six hundred sixty-four".