3878638065 has 24 divisors (see below), whose sum is σ = 6734356200. Its totient is φ = 2065104384.

The previous prime is 3878638063. The next prime is 3878638087. The reversal of 3878638065 is 5608368783.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 285474816 + 3593163249 = 16896^2 + 59943^2 .

It is not a de Polignac number, because 3878638065 - 2¹ = 3878638063 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (3878638063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45990 + ... + 99359.

It is an arithmetic number, because the mean of its divisors is an integer number (280598175).

Almost surely, 2^3878638065 is an apocalyptic number.

It is an amenable number.

3878638065 is a deficient number, since it is larger than the sum of its proper divisors (2855718135).

3878638065 is a wasteful number, since it uses less digits than its factorization.

3878638065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145953 (or 145950 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The square root of 3878638065 is about 62278.7127757149. The cubic root of 3878638065 is about 1571.1817228530.

The spelling of 3878638065 in words is "three billion, eight hundred seventy-eight million, six hundred thirty-eight thousand, sixty-five".