39681993 has 16 divisors (see below), whose sum is σ = 57276800. Its totient is φ = 24292224.

The previous prime is 39681949. The next prime is 39682003. The reversal of 39681993 is 39918693.

It is a happy number.

It is not a de Polignac number, because 39681993 - 2¹⁰ = 39680969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39681493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5205 + ... + 10317.

It is an arithmetic number, because the mean of its divisors is an integer number (3579800).

Almost surely, 2^39681993 is an apocalyptic number.

It is an amenable number.

39681993 is a deficient number, since it is larger than the sum of its proper divisors (17594807).

39681993 is a wasteful number, since it uses less digits than its factorization.

39681993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5328.

The product of its digits is 314928, while the sum is 48.

The square root of 39681993 is about 6299.3644917563. The cubic root of 39681993 is about 341.0864697023.

The spelling of 39681993 in words is "thirty-nine million, six hundred eighty-one thousand, nine hundred ninety-three".