6561870 has 32 divisors (see below), whose sum is σ = 17998848. Its totient is φ = 1499808.

The previous prime is 6561857. The next prime is 6561871. The reversal of 6561870 is 781656.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6561871) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15414 + ... + 15833.

It is an arithmetic number, because the mean of its divisors is an integer number (562464).

Almost surely, 2^6561870 is an apocalyptic number.

6561870 is an abundant number, since it is smaller than the sum of its proper divisors (11436978).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6561870 is a wasteful number, since it uses less digits than its factorization.

6561870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31264.

The product of its (nonzero) digits is 10080, while the sum is 33.

The square root of 6561870 is about 2561.6147251294. The cubic root of 6561870 is about 187.2158183908.

The spelling of 6561870 in words is "six million, five hundred sixty-one thousand, eight hundred seventy".