1098121309 has 2 divisors, whose sum is σ = 1098121310. Its totient is φ = 1098121308.

The previous prime is 1098121201. The next prime is 1098121331. The reversal of 1098121309 is 9031218901.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 890127225 + 207994084 = 29835^2 + 14422^2 .

It is a cyclic number.

It is not a de Polignac number, because 1098121309 - 2¹⁹ = 1097597021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1098121369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 549060654 + 549060655.

It is an arithmetic number, because the mean of its divisors is an integer number (549060655).

Almost surely, 2^1098121309 is an apocalyptic number.

It is an amenable number.

1098121309 is a deficient number, since it is larger than the sum of its proper divisors (1).

1098121309 is an equidigital number, since it uses as much as digits as its factorization.

1098121309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 1098121309 is about 33137.9134678090. The cubic root of 1098121309 is about 1031.6921031911.

The spelling of 1098121309 in words is "one billion, ninety-eight million, one hundred twenty-one thousand, three hundred nine".