7816565720413 has 2 divisors, whose sum is σ = 7816565720414. Its totient is φ = 7816565720412.

The previous prime is 7816565720387. The next prime is 7816565720437. The reversal of 7816565720413 is 3140275656187.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4997786638329 + 2818779082084 = 2235573^2 + 1678922^2 .

It is a cyclic number.

It is not a de Polignac number, because 7816565720413 - 2¹⁷ = 7816565589341 is a prime.

It is a super-2 number, since 2×7816565720413² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7816565720443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3908282860206 + 3908282860207.

It is an arithmetic number, because the mean of its divisors is an integer number (3908282860207).

Almost surely, 2^{7816565720413} is an apocalyptic number.

It is an amenable number.

7816565720413 is a deficient number, since it is larger than the sum of its proper divisors (1).

7816565720413 is an equidigital number, since it uses as much as digits as its factorization.

7816565720413 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8467200, while the sum is 55.

The spelling of 7816565720413 in words is "seven trillion, eight hundred sixteen billion, five hundred sixty-five million, seven hundred twenty thousand, four hundred thirteen".