39681940 has 24 divisors (see below), whose sum is σ = 83473992. Its totient is φ = 15845760.

The previous prime is 39681919. The next prime is 39681949. The reversal of 39681940 is 4918693.

It can be written as a sum of positive squares in 4 ways, for example, as 11102224 + 28579716 = 3332^2 + 5346^2 .

It is a junction number, because it is equal to n+sod(n) for n = 39681893 and 39681902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39681949) 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, 13830 + ... + 16450.

It is an arithmetic number, because the mean of its divisors is an integer number (3478083).

Almost surely, 2^39681940 is an apocalyptic number.

It is an amenable number.

39681940 is an abundant number, since it is smaller than the sum of its proper divisors (43792052).

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

39681940 is a wasteful number, since it uses less digits than its factorization.

39681940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3387 (or 3385 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 39681940 is about 6299.3602849813. The cubic root of 39681940 is about 341.0863178485.

The spelling of 39681940 in words is "thirty-nine million, six hundred eighty-one thousand, nine hundred forty".