2158857 has 6 divisors (see below), whose sum is σ = 3118362. Its totient is φ = 1439232.

The previous prime is 2158843. The next prime is 2158859. The reversal of 2158857 is 7588512.

2158857 is a `hidden beast` number, since 21 + 588 + 57 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2134521 + 24336 = 1461^2 + 156^2 .

It is not a de Polignac number, because 2158857 - 2⁴ = 2158841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2158859) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 119928 + ... + 119945.

It is an arithmetic number, because the mean of its divisors is an integer number (519727).

2^2158857 is an apocalyptic number.

It is an amenable number.

2158857 is a deficient number, since it is larger than the sum of its proper divisors (959505).

2158857 is a wasteful number, since it uses less digits than its factorization.

2158857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239879 (or 239876 counting only the distinct ones).

The product of its digits is 22400, while the sum is 36.

The square root of 2158857 is about 1469.3049377172. The cubic root of 2158857 is about 129.2432762784.

The spelling of 2158857 in words is "two million, one hundred fifty-eight thousand, eight hundred fifty-seven".