39664 has 20 divisors (see below), whose sum is σ = 80104. Its totient is φ = 19008.

The previous prime is 39659. The next prime is 39667. The reversal of 39664 is 46693.

39664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 11.

It is a nialpdrome in base 15.

It is a zygodrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39667) 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, 559 + ... + 625.

2³⁹⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

39664 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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 (40052).

39664 is a wasteful number, since it uses less digits than its factorization.

39664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 106 counting only the distinct ones).

The product of its digits is 3888, while the sum is 28.

The square root of 39664 is about 199.1582285521. The cubic root of 39664 is about 34.1034908980.

It can be divided in two parts, 39 and 664, that added together give a triangular number (703 = T₃₇).

The spelling of 39664 in words is "thirty-nine thousand, six hundred sixty-four".