6555581 has 2 divisors, whose sum is σ = 6555582. Its totient is φ = 6555580.

The previous prime is 6555547. The next prime is 6555611. The reversal of 6555581 is 1855556.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6528025 + 27556 = 2555^2 + 166^2 .

It is a cyclic number.

It is not a de Polignac number, because 6555581 - 2¹⁰ = 6554557 is a prime.

It is a super-2 number, since 2×6555581² = 85951284495122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6555541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3277790 + 3277791.

It is an arithmetic number, because the mean of its divisors is an integer number (3277791).

Almost surely, 2^6555581 is an apocalyptic number.

It is an amenable number.

6555581 is a deficient number, since it is larger than the sum of its proper divisors (1).

6555581 is an equidigital number, since it uses as much as digits as its factorization.

6555581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30000, while the sum is 35.

The square root of 6555581 is about 2560.3868848282. The cubic root of 6555581 is about 187.1559890724.

The spelling of 6555581 in words is "six million, five hundred fifty-five thousand, five hundred eighty-one".