3978936638 has 8 divisors (see below), whose sum is σ = 6057485832. Its totient is φ = 1959774696.

The previous prime is 3978936607. The next prime is 3978936667. The reversal of 3978936638 is 8366398793.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 14846645 + ... + 14846912.

It is an arithmetic number, because the mean of its divisors is an integer number (757185729).

Almost surely, 2^3978936638 is an apocalyptic number.

3978936638 is a deficient number, since it is larger than the sum of its proper divisors (2078549194).

3978936638 is a wasteful number, since it uses less digits than its factorization.

3978936638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29693626.

The product of its digits is 35271936, while the sum is 62.

The square root of 3978936638 is about 63078.8129089316. The cubic root of 3978936638 is about 1584.6098132308.

The spelling of 3978936638 in words is "three billion, nine hundred seventy-eight million, nine hundred thirty-six thousand, six hundred thirty-eight".