1021091 has 2 divisors, whose sum is σ = 1021092. Its totient is φ = 1021090.

The previous prime is 1021087. The next prime is 1021093. The reversal of 1021091 is 1901201.

It is a strong prime.

It is an emirp because it is prime and its reverse (1901201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1021091 - 2² = 1021087 is a prime.

Together with 1021093, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1021093) 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, 510545 + 510546.

It is an arithmetic number, because the mean of its divisors is an integer number (510546).

2^1021091 is an apocalyptic number.

1021091 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021091 is an equidigital number, since it uses as much as digits as its factorization.

1021091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 1021091 is about 1010.4904749675. The cubic root of 1021091 is about 100.6981478858.

Adding to 1021091 its reverse (1901201), we get a palindrome (2922292).

It can be divided in two parts, 10210 and 91, that added together give a palindrome (10301).

The spelling of 1021091 in words is "one million, twenty-one thousand, ninety-one".