2543656 has 8 divisors (see below), whose sum is σ = 4769370. Its totient is φ = 1271824.

The previous prime is 2543647. The next prime is 2543657. The reversal of 2543656 is 6563452.

It can be written as a sum of positive squares in only one way, i.e., 1602756 + 940900 = 1266^2 + 970^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (2543657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 158971 + ... + 158986.

2^2543656 is an apocalyptic number.

It is an amenable number.

2543656 is a deficient number, since it is larger than the sum of its proper divisors (2225714).

2543656 is a wasteful number, since it uses less digits than its factorization.

2543656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317963 (or 317959 counting only the distinct ones).

The product of its digits is 21600, while the sum is 31.

The square root of 2543656 is about 1594.8843218240. The cubic root of 2543656 is about 136.5063305754.

It can be divided in two parts, 25 and 43656, that added together give a square (43681 = 209²).

The spelling of 2543656 in words is "two million, five hundred forty-three thousand, six hundred fifty-six".