1891297 has 2 divisors, whose sum is σ = 1891298. Its totient is φ = 1891296.

The previous prime is 1891291. The next prime is 1891303. The reversal of 1891297 is 7921981.

It is a balanced prime because it is at equal distance from previous prime (1891291) and next prime (1891303).

It can be written as a sum of positive squares in only one way, i.e., 1115136 + 776161 = 1056^2 + 881^2 .

It is an emirp because it is prime and its reverse (7921981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1891297 - 2¹⁵ = 1858529 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1891291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945648 + 945649.

It is an arithmetic number, because the mean of its divisors is an integer number (945649).

2^1891297 is an apocalyptic number.

It is an amenable number.

1891297 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891297 is an equidigital number, since it uses as much as digits as its factorization.

1891297 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 37.

The square root of 1891297 is about 1375.2443419262. The cubic root of 1891297 is about 123.6668345751. Note that the first 3 decimals are identical.

The spelling of 1891297 in words is "one million, eight hundred ninety-one thousand, two hundred ninety-seven".