39780640 has 48 divisors (see below), whose sum is σ = 94885560. Its totient is φ = 15759360.

The previous prime is 39780617. The next prime is 39780641. The reversal of 39780640 is 4608793.

It can be written as a sum of positive squares in 4 ways, for example, as 36048016 + 3732624 = 6004^2 + 1932^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 39780640.

It is not an unprimeable number, because it can be changed into a prime (39780641) 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, 16300 + ... + 18580.

Almost surely, 2^39780640 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 39780640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47442780).

39780640 is an abundant number, since it is smaller than the sum of its proper divisors (55104920).

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

39780640 is a wasteful number, since it uses less digits than its factorization.

39780640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2405 (or 2397 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 39780640 is about 6307.1895484439. The cubic root of 39780640 is about 341.3688758291.

The spelling of 39780640 in words is "thirty-nine million, seven hundred eighty thousand, six hundred forty".