39987687 has 4 divisors (see below), whose sum is σ = 53316920. Its totient is φ = 26658456.

The previous prime is 39987653. The next prime is 39987733. The reversal of 39987687 is 78678993.

39987687 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 39987687 - 2⁷ = 39987559 is a prime.

It is a super-2 number, since 2×39987687² = 3198030223219938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39987637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6664612 + ... + 6664617.

It is an arithmetic number, because the mean of its divisors is an integer number (13329230).

Almost surely, 2^39987687 is an apocalyptic number.

39987687 is a deficient number, since it is larger than the sum of its proper divisors (13329233).

39987687 is a wasteful number, since it uses less digits than its factorization.

39987687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13329232.

The product of its digits is 4572288, while the sum is 57.

The square root of 39987687 is about 6323.5818172931. The cubic root of 39987687 is about 341.9600941777.

The spelling of 39987687 in words is "thirty-nine million, nine hundred eighty-seven thousand, six hundred eighty-seven".