1020989 has 2 divisors, whose sum is σ = 1020990. Its totient is φ = 1020988.

The previous prime is 1020979. The next prime is 1020991. The reversal of 1020989 is 9890201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 940900 + 80089 = 970^2 + 283^2 .

It is an emirp because it is prime and its reverse (9890201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1020989 - 2⁴ = 1020973 is a prime.

Together with 1020991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1020959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510494 + 510495.

It is an arithmetic number, because the mean of its divisors is an integer number (510495).

2^1020989 is an apocalyptic number.

It is an amenable number.

1020989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020989 is an equidigital number, since it uses as much as digits as its factorization.

1020989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 1020989 is about 1010.4400031669. The cubic root of 1020989 is about 100.6947947556.

The spelling of 1020989 in words is "one million, twenty thousand, nine hundred eighty-nine".