1391057 has 2 divisors, whose sum is σ = 1391058. Its totient is φ = 1391056.

The previous prime is 1391051. The next prime is 1391081. The reversal of 1391057 is 7501931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1032256 + 358801 = 1016^2 + 599^2 .

It is a cyclic number.

It is not a de Polignac number, because 1391057 - 2⁴ = 1391041 is a prime.

It is not a weakly prime, because it can be changed into another prime (1391051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695528 + 695529.

It is an arithmetic number, because the mean of its divisors is an integer number (695529).

2^1391057 is an apocalyptic number.

It is an amenable number.

1391057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1391057 is an equidigital number, since it uses as much as digits as its factorization.

1391057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 945, while the sum is 26.

The square root of 1391057 is about 1179.4307949176. The cubic root of 1391057 is about 111.6301843645.

Adding to 1391057 its reverse (7501931), we get a palindrome (8892988).

The spelling of 1391057 in words is "one million, three hundred ninety-one thousand, fifty-seven".