1020209987 has 2 divisors, whose sum is σ = 1020209988. Its totient is φ = 1020209986.

The previous prime is 1020209941. The next prime is 1020210019. The reversal of 1020209987 is 7899020201.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1020209987 - 2¹⁰ = 1020208963 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1020209987.

It is not a weakly prime, because it can be changed into another prime (1020205987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510104993 + 510104994.

It is an arithmetic number, because the mean of its divisors is an integer number (510104994).

Almost surely, 2^1020209987 is an apocalyptic number.

1020209987 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020209987 is an equidigital number, since it uses as much as digits as its factorization.

1020209987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 1020209987 is about 31940.7261501676. The cubic root of 1020209987 is about 1006.6917824945.

The spelling of 1020209987 in words is "one billion, twenty million, two hundred nine thousand, nine hundred eighty-seven".