6561650 has 24 divisors (see below), whose sum is σ = 12848880. Its totient is φ = 2486160.

The previous prime is 6561649. The next prime is 6561673. The reversal of 6561650 is 561656.

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

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2504 + ... + 4403.

It is an arithmetic number, because the mean of its divisors is an integer number (535370).

Almost surely, 2^6561650 is an apocalyptic number.

6561650 is a deficient number, since it is larger than the sum of its proper divisors (6287230).

6561650 is a wasteful number, since it uses less digits than its factorization.

6561650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6938 (or 6933 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 6561650 is about 2561.5717831051. The cubic root of 6561650 is about 187.2137261041.

The spelling of 6561650 in words is "six million, five hundred sixty-one thousand, six hundred fifty".