6556551 has 4 divisors (see below), whose sum is σ = 8742072. Its totient is φ = 4371032.

The previous prime is 6556519. The next prime is 6556559. The reversal of 6556551 is 1556556.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6556551 - 2⁵ = 6556519 is a prime.

It is a super-2 number, since 2×6556551² = 85976722031202, which contains 22 as substring.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6556559) 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, 1092756 + ... + 1092761.

It is an arithmetic number, because the mean of its divisors is an integer number (2185518).

Almost surely, 2^6556551 is an apocalyptic number.

6556551 is a deficient number, since it is larger than the sum of its proper divisors (2185521).

6556551 is a wasteful number, since it uses less digits than its factorization.

6556551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2185520.

The product of its digits is 22500, while the sum is 33.

The square root of 6556551 is about 2560.5763023195. The cubic root of 6556551 is about 187.1652194954.

It can be divided in two parts, 65 and 56551, that added together give a triangular number (56616 = T₃₃₆).

The spelling of 6556551 in words is "six million, five hundred fifty-six thousand, five hundred fifty-one".