39780 has 72 divisors (see below), whose sum is σ = 137592. Its totient is φ = 9216.

The previous prime is 39779. The next prime is 39791. The reversal of 39780 is 8793.

It is a happy number.

39780 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 2916 + 36864 = 54^2 + 192^2 .

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a zygodrome in base 8.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2332 + ... + 2348.

It is an arithmetic number, because the mean of its divisors is an integer number (1911).

2³⁹⁷⁸⁰ is an apocalyptic number.

39780 is a gapful number since it is divisible by the number (30) 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 39780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68796).

39780 is an abundant number, since it is smaller than the sum of its proper divisors (97812).

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

39780 is a wasteful number, since it uses less digits than its factorization.

39780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 39780 is about 199.4492416631. The cubic root of 39780 is about 34.1367045146.

The spelling of 39780 in words is "thirty-nine thousand, seven hundred eighty".