2157856 has 12 divisors (see below), whose sum is σ = 4248342. Its totient is φ = 1078912.

The previous prime is 2157851. The next prime is 2157863. The reversal of 2157856 is 6587512.

It can be written as a sum of positive squares in only one way, i.e., 1690000 + 467856 = 1300^2 + 684^2 .

It is not an unprimeable number, because it can be changed into a prime (2157851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33685 + ... + 33748.

2^2157856 is an apocalyptic number.

It is an amenable number.

2157856 is a deficient number, since it is larger than the sum of its proper divisors (2090486).

2157856 is an equidigital number, since it uses as much as digits as its factorization.

2157856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67443 (or 67435 counting only the distinct ones).

The product of its digits is 16800, while the sum is 34.

The square root of 2157856 is about 1468.9642609676. The cubic root of 2157856 is about 129.2232977249.

The spelling of 2157856 in words is "two million, one hundred fifty-seven thousand, eight hundred fifty-six".