1206728449909 has 2 divisors, whose sum is σ = 1206728449910. Its totient is φ = 1206728449908.

The previous prime is 1206728449811. The next prime is 1206728449933. The reversal of 1206728449909 is 9099448276021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1126404387684 + 80324062225 = 1061322^2 + 283415^2 .

It is a cyclic number.

It is not a de Polignac number, because 1206728449909 - 2¹³ = 1206728441717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1206728449009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 603364224954 + 603364224955.

It is an arithmetic number, because the mean of its divisors is an integer number (603364224955).

Almost surely, 2^{1206728449909} is an apocalyptic number.

It is an amenable number.

1206728449909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1206728449909 is an equidigital number, since it uses as much as digits as its factorization.

1206728449909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15676416, while the sum is 61.

The spelling of 1206728449909 in words is "one trillion, two hundred six billion, seven hundred twenty-eight million, four hundred forty-nine thousand, nine hundred nine".