8120857 has 4 divisors (see below), whose sum is σ = 8133840. Its totient is φ = 8107876.

The previous prime is 8120843. The next prime is 8120867. The reversal of 8120857 is 7580218.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8120857 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8120807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5503 + ... + 6820.

It is an arithmetic number, because the mean of its divisors is an integer number (2033460).

Almost surely, 2^8120857 is an apocalyptic number.

It is an amenable number.

8120857 is a deficient number, since it is larger than the sum of its proper divisors (12983).

8120857 is a wasteful number, since it uses less digits than its factorization.

8120857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12982.

The product of its (nonzero) digits is 4480, while the sum is 31.

The square root of 8120857 is about 2849.7117398081. The cubic root of 8120857 is about 201.0021121367.

The spelling of 8120857 in words is "eight million, one hundred twenty thousand, eight hundred fifty-seven".