6857821344257 has 8 divisors (see below), whose sum is σ = 7542481086336. Its totient is φ = 6195609462672.

The previous prime is 6857821344251. The next prime is 6857821344277. The reversal of 6857821344257 is 7524431287586.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 6857821344257 - 2⁶ = 6857821344193 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6857821344257.

It is not an unprimeable number, because it can be changed into a prime (6857821344251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5611964483 + ... + 5611965704.

It is an arithmetic number, because the mean of its divisors is an integer number (942810135792).

Almost surely, 2^{6857821344257} is an apocalyptic number.

It is an amenable number.

6857821344257 is a deficient number, since it is larger than the sum of its proper divisors (684659742079).

6857821344257 is a wasteful number, since it uses less digits than its factorization.

6857821344257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11223930247.

The product of its digits is 90316800, while the sum is 62.

The spelling of 6857821344257 in words is "six trillion, eight hundred fifty-seven billion, eight hundred twenty-one million, three hundred forty-four thousand, two hundred fifty-seven".