1320221012261 has 2 divisors, whose sum is σ = 1320221012262. Its totient is φ = 1320221012260.

The previous prime is 1320221012219. The next prime is 1320221012269. The reversal of 1320221012261 is 1622101220231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1319066032036 + 1154980225 = 1148506^2 + 33985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1320221012261 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1320221012269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660110506130 + 660110506131.

It is an arithmetic number, because the mean of its divisors is an integer number (660110506131).

Almost surely, 2^{1320221012261} is an apocalyptic number.

It is an amenable number.

1320221012261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320221012261 is an equidigital number, since it uses as much as digits as its factorization.

1320221012261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 1320221012261 its reverse (1622101220231), we get a palindrome (2942322232492).

The spelling of 1320221012261 in words is "one trillion, three hundred twenty billion, two hundred twenty-one million, twelve thousand, two hundred sixty-one".