1028919989 has 2 divisors, whose sum is σ = 1028919990. Its totient is φ = 1028919988.

The previous prime is 1028919979. The next prime is 1028920003. The reversal of 1028919989 is 9899198201.

1028919989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1008062500 + 20857489 = 31750^2 + 4567^2 .

It is an emirp because it is prime and its reverse (9899198201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1028919989 - 2²⁸ = 760484533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1028919919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 514459994 + 514459995.

It is an arithmetic number, because the mean of its divisors is an integer number (514459995).

Almost surely, 2^1028919989 is an apocalyptic number.

It is an amenable number.

1028919989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1028919989 is an equidigital number, since it uses as much as digits as its factorization.

1028919989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 839808, while the sum is 56.

The square root of 1028919989 is about 32076.7827096172. The cubic root of 1028919989 is about 1009.5485316820.

The spelling of 1028919989 in words is "one billion, twenty-eight million, nine hundred nineteen thousand, nine hundred eighty-nine".