1289228849 has 2 divisors, whose sum is σ = 1289228850. Its totient is φ = 1289228848.

The previous prime is 1289228819. The next prime is 1289228861. The reversal of 1289228849 is 9488229821.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1138725025 + 150503824 = 33745^2 + 12268^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1289228849 is a prime.

It is a super-2 number, since 2×1289228849² = 3324222050187729602, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1289228849.

It is not a weakly prime, because it can be changed into another prime (1289228819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 644614424 + 644614425.

It is an arithmetic number, because the mean of its divisors is an integer number (644614425).

Almost surely, 2^1289228849 is an apocalyptic number.

It is an amenable number.

1289228849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1289228849 is an equidigital number, since it uses as much as digits as its factorization.

1289228849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1327104, while the sum is 53.

The square root of 1289228849 is about 35905.8330776491. The cubic root of 1289228849 is about 1088.3702741598.

The spelling of 1289228849 in words is "one billion, two hundred eighty-nine million, two hundred twenty-eight thousand, eight hundred forty-nine".