1305315101621 has 2 divisors, whose sum is σ = 1305315101622. Its totient is φ = 1305315101620.

The previous prime is 1305315101509. The next prime is 1305315101669. The reversal of 1305315101621 is 1261015135031.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 775833302596 + 529481799025 = 880814^2 + 727655^2 .

It is an emirp because it is prime and its reverse (1261015135031) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1305315101621 - 2¹⁴ = 1305315085237 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 (1305315101821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 652657550810 + 652657550811.

It is an arithmetic number, because the mean of its divisors is an integer number (652657550811).

Almost surely, 2^{1305315101621} is an apocalyptic number.

It is an amenable number.

1305315101621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1305315101621 is an equidigital number, since it uses as much as digits as its factorization.

1305315101621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2700, while the sum is 29.

The spelling of 1305315101621 in words is "one trillion, three hundred five billion, three hundred fifteen million, one hundred one thousand, six hundred twenty-one".