3878391 has 16 divisors (see below), whose sum is σ = 5678208. Its totient is φ = 2335200.

The previous prime is 3878389. The next prime is 3878401. The reversal of 3878391 is 1938783.

It is not a de Polignac number, because 3878391 - 2¹ = 3878389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3878291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6685 + ... + 7241.

It is an arithmetic number, because the mean of its divisors is an integer number (354888).

Almost surely, 2^3878391 is an apocalyptic number.

3878391 is a deficient number, since it is larger than the sum of its proper divisors (1799817).

3878391 is a wasteful number, since it uses less digits than its factorization.

3878391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782.

The product of its digits is 36288, while the sum is 39.

The square root of 3878391 is about 1969.3630950132. The cubic root of 3878391 is about 157.1148361293.

It can be divided in two parts, 38783 and 91, that multiplied together give a palindrome (3529253).

The spelling of 3878391 in words is "three million, eight hundred seventy-eight thousand, three hundred ninety-one".