6557643 has 6 divisors (see below), whose sum is σ = 9472164. Its totient is φ = 4371756.

The previous prime is 6557623. The next prime is 6557651. The reversal of 6557643 is 3467556.

6557643 is a `hidden beast` number, since 6 + 5 + 5 + 7 + 643 = 666.

It is not a de Polignac number, because 6557643 - 2²⁰ = 5509067 is a prime.

6557643 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 6557598 and 6557607.

It is not an unprimeable number, because it can be changed into a prime (6557623) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 364305 + ... + 364322.

It is an arithmetic number, because the mean of its divisors is an integer number (1578694).

Almost surely, 2^6557643 is an apocalyptic number.

6557643 is a deficient number, since it is larger than the sum of its proper divisors (2914521).

6557643 is a wasteful number, since it uses less digits than its factorization.

6557643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728633 (or 728630 counting only the distinct ones).

The product of its digits is 75600, while the sum is 36.

The square root of 6557643 is about 2560.7895266890. The cubic root of 6557643 is about 187.1756097689.

The spelling of 6557643 in words is "six million, five hundred fifty-seven thousand, six hundred forty-three".