3978345 has 16 divisors (see below), whose sum is σ = 7274880. Its totient is φ = 1818624.

The previous prime is 3978329. The next prime is 3978349. The reversal of 3978345 is 5438793.

It is not a de Polignac number, because 3978345 - 2⁴ = 3978329 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3978349) 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, 18840 + ... + 19049.

It is an arithmetic number, because the mean of its divisors is an integer number (454680).

Almost surely, 2^3978345 is an apocalyptic number.

3978345 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

3978345 is a deficient number, since it is larger than the sum of its proper divisors (3296535).

3978345 is a wasteful number, since it uses less digits than its factorization.

3978345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37904.

The product of its digits is 90720, while the sum is 39.

The square root of 3978345 is about 1994.5789029266. The cubic root of 3978345 is about 158.4531269478.

The spelling of 3978345 in words is "three million, nine hundred seventy-eight thousand, three hundred forty-five".