1678216369 has 2 divisors, whose sum is σ = 1678216370. Its totient is φ = 1678216368.

The previous prime is 1678216313. The next prime is 1678216373. The reversal of 1678216369 is 9636128761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1433606769 + 244609600 = 37863^2 + 15640^2 .

It is a cyclic number.

It is not a de Polignac number, because 1678216369 - 2¹³ = 1678208177 is a prime.

It is a super-2 number, since 2×1678216369² = 5632820362359088322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1678216669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 839108184 + 839108185.

It is an arithmetic number, because the mean of its divisors is an integer number (839108185).

Almost surely, 2^1678216369 is an apocalyptic number.

It is an amenable number.

1678216369 is a deficient number, since it is larger than the sum of its proper divisors (1).

1678216369 is an equidigital number, since it uses as much as digits as its factorization.

1678216369 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 653184, while the sum is 49.

The square root of 1678216369 is about 40966.0392154282. The cubic root of 1678216369 is about 1188.3635366803.

The spelling of 1678216369 in words is "one billion, six hundred seventy-eight million, two hundred sixteen thousand, three hundred sixty-nine".