7981792581409 has 2 divisors, whose sum is σ = 7981792581410. Its totient is φ = 7981792581408.

The previous prime is 7981792581397. The next prime is 7981792581443. The reversal of 7981792581409 is 9041852971897.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7013678272225 + 968114309184 = 2648335^2 + 983928^2 .

It is a cyclic number.

It is not a de Polignac number, because 7981792581409 - 2¹¹ = 7981792579361 is a prime.

It is not a weakly prime, because it can be changed into another prime (7981792581709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3990896290704 + 3990896290705.

It is an arithmetic number, because the mean of its divisors is an integer number (3990896290705).

Almost surely, 2^{7981792581409} is an apocalyptic number.

It is an amenable number.

7981792581409 is a deficient number, since it is larger than the sum of its proper divisors (1).

7981792581409 is an equidigital number, since it uses as much as digits as its factorization.

7981792581409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 91445760, while the sum is 70.

The spelling of 7981792581409 in words is "seven trillion, nine hundred eighty-one billion, seven hundred ninety-two million, five hundred eighty-one thousand, four hundred nine".