39681013 has 4 divisors (see below), whose sum is σ = 39724300. Its totient is φ = 39637728.

The previous prime is 39681011. The next prime is 39681017. The reversal of 39681013 is 31018693.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20958084 + 18722929 = 4578^2 + 4327^2 .

It is a cyclic number.

It is not a de Polignac number, because 39681013 - 2¹ = 39681011 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39681011) 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, 20238 + ... + 22111.

It is an arithmetic number, because the mean of its divisors is an integer number (9931075).

Almost surely, 2^39681013 is an apocalyptic number.

It is an amenable number.

39681013 is a deficient number, since it is larger than the sum of its proper divisors (43287).

39681013 is an equidigital number, since it uses as much as digits as its factorization.

39681013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43286.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 39681013 is about 6299.2867056517. The cubic root of 39681013 is about 341.0836618167.

The spelling of 39681013 in words is "thirty-nine million, six hundred eighty-one thousand, thirteen".