2857861 has 2 divisors, whose sum is σ = 2857862. Its totient is φ = 2857860.

The previous prime is 2857849. The next prime is 2857867. The reversal of 2857861 is 1687582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2340900 + 516961 = 1530^2 + 719^2 .

It is a cyclic number.

It is not a de Polignac number, because 2857861 - 2¹³ = 2849669 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2857861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2857867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1428930 + 1428931.

It is an arithmetic number, because the mean of its divisors is an integer number (1428931).

2^2857861 is an apocalyptic number.

It is an amenable number.

2857861 is a deficient number, since it is larger than the sum of its proper divisors (1).

2857861 is an equidigital number, since it uses as much as digits as its factorization.

2857861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26880, while the sum is 37.

The square root of 2857861 is about 1690.5209256321. The cubic root of 2857861 is about 141.9102289171.

The spelling of 2857861 in words is "two million, eight hundred fifty-seven thousand, eight hundred sixty-one".