1331857 has 2 divisors, whose sum is σ = 1331858. Its totient is φ = 1331856.

The previous prime is 1331851. The next prime is 1331921. The reversal of 1331857 is 7581331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1324801 + 7056 = 1151^2 + 84^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1331857 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1331851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665928 + 665929.

It is an arithmetic number, because the mean of its divisors is an integer number (665929).

2^1331857 is an apocalyptic number.

It is an amenable number.

1331857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331857 is an equidigital number, since it uses as much as digits as its factorization.

1331857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 28.

The square root of 1331857 is about 1154.0610902374. The cubic root of 1331857 is about 110.0236037502.

It can be divided in two parts, 133185 and 7, that multiplied together give a triangular number (932295 = T₁₃₆₅).

The spelling of 1331857 in words is "one million, three hundred thirty-one thousand, eight hundred fifty-seven".