1019128909 has 2 divisors, whose sum is σ = 1019128910. Its totient is φ = 1019128908.

The previous prime is 1019128879. The next prime is 1019128921. The reversal of 1019128909 is 9098219101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 534996900 + 484132009 = 23130^2 + 22003^2 .

It is a cyclic number.

It is not a de Polignac number, because 1019128909 - 2²³ = 1010740301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1019128969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 509564454 + 509564455.

It is an arithmetic number, because the mean of its divisors is an integer number (509564455).

Almost surely, 2^1019128909 is an apocalyptic number.

It is an amenable number.

1019128909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1019128909 is an equidigital number, since it uses as much as digits as its factorization.

1019128909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 40.

The square root of 1019128909 is about 31923.7984738659. The cubic root of 1019128909 is about 1006.3360723976.

The spelling of 1019128909 in words is "one billion, nineteen million, one hundred twenty-eight thousand, nine hundred nine".