16208785517 has 2 divisors, whose sum is σ = 16208785518. Its totient is φ = 16208785516.

The previous prime is 16208785501. The next prime is 16208785583. The reversal of 16208785517 is 71558780261.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16123666441 + 85119076 = 126979^2 + 9226^2 .

It is a cyclic number.

It is not a de Polignac number, because 16208785517 - 2⁴ = 16208785501 is a prime.

It is a super-2 number, since 2×16208785517² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16208785217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8104392758 + 8104392759.

It is an arithmetic number, because the mean of its divisors is an integer number (8104392759).

Almost surely, 2^16208785517 is an apocalyptic number.

It is an amenable number.

16208785517 is a deficient number, since it is larger than the sum of its proper divisors (1).

16208785517 is an equidigital number, since it uses as much as digits as its factorization.

16208785517 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 940800, while the sum is 50.

The spelling of 16208785517 in words is "sixteen billion, two hundred eight million, seven hundred eighty-five thousand, five hundred seventeen".