3978819 has 24 divisors (see below), whose sum is σ = 6394752. Its totient is φ = 2367360.

The previous prime is 3978817. The next prime is 3978823. The reversal of 3978819 is 9188793.

It is not a de Polignac number, because 3978819 - 2¹ = 3978817 is a prime.

It is a super-2 number, since 2×3978819² = 31662001269522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (3978811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3079 + ... + 4175.

It is an arithmetic number, because the mean of its divisors is an integer number (266448).

Almost surely, 2^3978819 is an apocalyptic number.

3978819 is a gapful number since it is divisible by the number (39) formed by its first and last digit.

3978819 is a deficient number, since it is larger than the sum of its proper divisors (2415933).

3978819 is a wasteful number, since it uses less digits than its factorization.

3978819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147 (or 1144 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 3978819 is about 1994.6977214606. The cubic root of 3978819 is about 158.4594196649.

It can be divided in two parts, 397 and 8819, that added together give a square (9216 = 96²).

The spelling of 3978819 in words is "three million, nine hundred seventy-eight thousand, eight hundred nineteen".