16378887916817 has 2 divisors, whose sum is σ = 16378887916818. Its totient is φ = 16378887916816.

The previous prime is 16378887916753. The next prime is 16378887916871. The reversal of 16378887916817 is 71861978887361.

16378887916817 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (16378887916871) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9122550366736 + 7256337550081 = 3020356^2 + 2693759^2 .

It is a cyclic number.

It is not a de Polignac number, because 16378887916817 - 2⁶ = 16378887916753 is a prime.

It is a super-2 number, since 2×16378887916817² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16378887916117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8189443958408 + 8189443958409.

It is an arithmetic number, because the mean of its divisors is an integer number (8189443958409).

Almost surely, 2^{16378887916817} is an apocalyptic number.

It is an amenable number.

16378887916817 is a deficient number, since it is larger than the sum of its proper divisors (1).

16378887916817 is an equidigital number, since it uses as much as digits as its factorization.

16378887916817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1365590016, while the sum is 80.

The spelling of 16378887916817 in words is "sixteen trillion, three hundred seventy-eight billion, eight hundred eighty-seven million, nine hundred sixteen thousand, eight hundred seventeen".