1099787989 has 2 divisors, whose sum is σ = 1099787990. Its totient is φ = 1099787988.

The previous prime is 1099787957. The next prime is 1099788031. The reversal of 1099787989 is 9897879901.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 584043889 + 515744100 = 24167^2 + 22710^2 .

It is a cyclic number.

It is not a de Polignac number, because 1099787989 - 2⁵ = 1099787957 is a prime.

It is a zygodrome in base 3.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1099787189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 549893994 + 549893995.

It is an arithmetic number, because the mean of its divisors is an integer number (549893995).

Almost surely, 2^1099787989 is an apocalyptic number.

It is an amenable number.

1099787989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1099787989 is an equidigital number, since it uses as much as digits as its factorization.

1099787989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20575296, while the sum is 67.

The square root of 1099787989 is about 33163.0515634493. The cubic root of 1099787989 is about 1032.2137915771.

The spelling of 1099787989 in words is "one billion, ninety-nine million, seven hundred eighty-seven thousand, nine hundred eighty-nine".