6857561 has 4 divisors (see below), whose sum is σ = 6862800. Its totient is φ = 6852324.

The previous prime is 6857551. The next prime is 6857567. The reversal of 6857561 is 1657586.

It is a happy number.

6857561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6857561 - 2⁶ = 6857497 is a prime.

It is a super-2 number, since 2×6857561² = 94052285737442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6857567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1250 + ... + 3908.

It is an arithmetic number, because the mean of its divisors is an integer number (1715700).

Almost surely, 2^6857561 is an apocalyptic number.

It is an amenable number.

6857561 is a deficient number, since it is larger than the sum of its proper divisors (5239).

6857561 is a wasteful number, since it uses less digits than its factorization.

6857561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5238.

The product of its digits is 50400, while the sum is 38.

The square root of 6857561 is about 2618.6945220854. The cubic root of 6857561 is about 189.9867119054.

The spelling of 6857561 in words is "six million, eight hundred fifty-seven thousand, five hundred sixty-one".