1021387 has 2 divisors, whose sum is σ = 1021388. Its totient is φ = 1021386.

The previous prime is 1021381. The next prime is 1021403. The reversal of 1021387 is 7831201.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1021387 - 2⁷ = 1021259 is a prime.

It is an Ulam number.

1021387 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (1021381) 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, 510693 + 510694.

It is an arithmetic number, because the mean of its divisors is an integer number (510694).

2^1021387 is an apocalyptic number.

1021387 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021387 is an equidigital number, since it uses as much as digits as its factorization.

1021387 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 1021387 is about 1010.6369278826. The cubic root of 1021387 is about 100.7078772740.

Adding to 1021387 its reverse (7831201), we get a palindrome (8852588).

The spelling of 1021387 in words is "one million, twenty-one thousand, three hundred eighty-seven".