1021291 has 2 divisors, whose sum is σ = 1021292. Its totient is φ = 1021290.

The previous prime is 1021289. The next prime is 1021297. The reversal of 1021291 is 1921201.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1021291 - 2¹ = 1021289 is a prime.

Together with 1021289, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1021297) 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, 510645 + 510646.

It is an arithmetic number, because the mean of its divisors is an integer number (510646).

2^1021291 is an apocalyptic number.

1021291 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021291 is an equidigital number, since it uses as much as digits as its factorization.

1021291 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 1021291 is about 1010.5894319653. The cubic root of 1021291 is about 100.7047220027.

Adding to 1021291 its reverse (1921201), we get a palindrome (2942492).

The spelling of 1021291 in words is "one million, twenty-one thousand, two hundred ninety-one".