20380621649309 has 2 divisors, whose sum is σ = 20380621649310. Its totient is φ = 20380621649308.

The previous prime is 20380621649263. The next prime is 20380621649359. The reversal of 20380621649309 is 90394612608302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20257002605284 + 123619044025 = 4500778^2 + 351595^2 .

It is a cyclic number.

It is not a de Polignac number, because 20380621649309 - 2⁸ = 20380621649053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20380621649359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10190310824654 + 10190310824655.

It is an arithmetic number, because the mean of its divisors is an integer number (10190310824655).

Almost surely, 2^{20380621649309} is an apocalyptic number.

It is an amenable number.

20380621649309 is a deficient number, since it is larger than the sum of its proper divisors (1).

20380621649309 is an equidigital number, since it uses as much as digits as its factorization.

20380621649309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3359232, while the sum is 53.

The spelling of 20380621649309 in words is "twenty trillion, three hundred eighty billion, six hundred twenty-one million, six hundred forty-nine thousand, three hundred nine".