3643856 has 20 divisors (see below), whose sum is σ = 7194852. Its totient is φ = 1787136.

The previous prime is 3643853. The next prime is 3643859. The reversal of 3643856 is 6583463.

3643856 = T₃₄₄ + T₃₄₅ + ... + T₃₉₆.

It is an interprime number because it is at equal distance from previous prime (3643853) and next prime (3643859).

It can be written as a sum of positive squares in 2 ways, for example, as 2298256 + 1345600 = 1516^2 + 1160^2 .

It is a super-3 number, since 3×3643856³ (a number of 21 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3643853) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1301 + ... + 2996.

Almost surely, 2^3643856 is an apocalyptic number.

It is an amenable number.

3643856 is a deficient number, since it is larger than the sum of its proper divisors (3550996).

3643856 is a wasteful number, since it uses less digits than its factorization.

3643856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4358 (or 4352 counting only the distinct ones).

The product of its digits is 51840, while the sum is 35.

The square root of 3643856 is about 1908.8886819299. Note that the first 3 decimals coincide. The cubic root of 3643856 is about 153.8817330019.

The spelling of 3643856 in words is "three million, six hundred forty-three thousand, eight hundred fifty-six".