71664 has 20 divisors (see below), whose sum is σ = 185256. Its totient is φ = 23872.

The previous prime is 71663. The next prime is 71671. The reversal of 71664 is 46617.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 699 + ... + 794.

2⁷¹⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

71664 is an abundant number, since it is smaller than the sum of its proper divisors (113592).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92628).

71664 is a wasteful number, since it uses less digits than its factorization.

71664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1504 (or 1498 counting only the distinct ones).

The product of its digits is 1008, while the sum is 24.

The square root of 71664 is about 267.7013261080. The cubic root of 71664 is about 41.5368618145.

It can be divided in two parts, 716 and 64, that added together give a triangular number (780 = T₃₉).

The spelling of 71664 in words is "seventy-one thousand, six hundred sixty-four".