3997856 has 24 divisors (see below), whose sum is σ = 8334900. Its totient is φ = 1881088.

The previous prime is 3997849. The next prime is 3997859. The reversal of 3997856 is 6587993.

It can be written as a sum of positive squares in 2 ways, for example, as 3763600 + 234256 = 1940^2 + 484^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 3997856.

It is not an unprimeable number, because it can be changed into a prime (3997859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3131 + ... + 4218.

Almost surely, 2^3997856 is an apocalyptic number.

It is an amenable number.

3997856 is an abundant number, since it is smaller than the sum of its proper divisors (4337044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3997856 is a wasteful number, since it uses less digits than its factorization.

3997856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7376 (or 7368 counting only the distinct ones).

The product of its digits is 408240, while the sum is 47.

The square root of 3997856 is about 1999.4639281567. The cubic root of 3997856 is about 158.7117385626.

The spelling of 3997856 in words is "three million, nine hundred ninety-seven thousand, eight hundred fifty-six".