6857421 has 8 divisors (see below), whose sum is σ = 9166080. Its totient is φ = 4560192.

The previous prime is 6857419. The next prime is 6857429. The reversal of 6857421 is 1247586.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6857421 - 2¹ = 6857419 is a prime.

It is an Ulam number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6857429) 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 7 ways as a sum of consecutive naturals, for example, 1341 + ... + 3938.

It is an arithmetic number, because the mean of its divisors is an integer number (1145760).

Almost surely, 2^6857421 is an apocalyptic number.

It is an amenable number.

6857421 is a deficient number, since it is larger than the sum of its proper divisors (2308659).

6857421 is a wasteful number, since it uses less digits than its factorization.

6857421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5715.

The product of its digits is 13440, while the sum is 33.

The square root of 6857421 is about 2618.6677910724. The cubic root of 6857421 is about 189.9854190103.

The spelling of 6857421 in words is "six million, eight hundred fifty-seven thousand, four hundred twenty-one".