3978239 has 4 divisors (see below), whose sum is σ = 4187640. Its totient is φ = 3768840.

The previous prime is 3978229. The next prime is 3978253. The reversal of 3978239 is 9328793.

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

It is not a de Polignac number, because 3978239 - 2¹² = 3974143 is a prime.

It is a super-2 number, since 2×3978239² = 31652771082242, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3978196 and 3978205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3978229) by changing a digit.

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, 104672 + ... + 104709.

It is an arithmetic number, because the mean of its divisors is an integer number (1046910).

Almost surely, 2^3978239 is an apocalyptic number.

3978239 is a deficient number, since it is larger than the sum of its proper divisors (209401).

3978239 is a wasteful number, since it uses less digits than its factorization.

3978239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209400.

The product of its digits is 81648, while the sum is 41.

The square root of 3978239 is about 1994.5523307249. The cubic root of 3978239 is about 158.4517196473.

The spelling of 3978239 in words is "three million, nine hundred seventy-eight thousand, two hundred thirty-nine".