1021897 has 2 divisors, whose sum is σ = 1021898. Its totient is φ = 1021896.

The previous prime is 1021879. The next prime is 1021907. The reversal of 1021897 is 7981201.

Together with previous prime (1021879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 962361 + 59536 = 981^2 + 244^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021897 - 2¹¹ = 1019849 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021807) 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, 510948 + 510949.

It is an arithmetic number, because the mean of its divisors is an integer number (510949).

2^1021897 is an apocalyptic number.

It is an amenable number.

1021897 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021897 is an equidigital number, since it uses as much as digits as its factorization.

1021897 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 1021897 is about 1010.8892125253. The cubic root of 1021897 is about 100.7246363383.

The spelling of 1021897 in words is "one million, twenty-one thousand, eight hundred ninety-seven".