1684878289 has 2 divisors, whose sum is σ = 1684878290. Its totient is φ = 1684878288.

The previous prime is 1684878259. The next prime is 1684878319. The reversal of 1684878289 is 9828784861.

It is a balanced prime because it is at equal distance from previous prime (1684878259) and next prime (1684878319).

It can be written as a sum of positive squares in only one way, i.e., 1491890625 + 192987664 = 38625^2 + 13892^2 .

It is a cyclic number.

It is not a de Polignac number, because 1684878289 - 2⁷ = 1684878161 is a prime.

It is not a weakly prime, because it can be changed into another prime (1684878259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 842439144 + 842439145.

It is an arithmetic number, because the mean of its divisors is an integer number (842439145).

Almost surely, 2^1684878289 is an apocalyptic number.

It is an amenable number.

1684878289 is a deficient number, since it is larger than the sum of its proper divisors (1).

1684878289 is an equidigital number, since it uses as much as digits as its factorization.

1684878289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12386304, while the sum is 61.

The square root of 1684878289 is about 41047.2689590915. The cubic root of 1684878289 is about 1189.9339202532.

The spelling of 1684878289 in words is "one billion, six hundred eighty-four million, eight hundred seventy-eight thousand, two hundred eighty-nine".