1688213 has 2 divisors, whose sum is σ = 1688214. Its totient is φ = 1688212.

The previous prime is 1688201. The next prime is 1688231. The reversal of 1688213 is 3128861.

Together with next prime (1688231) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1435204 + 253009 = 1198^2 + 503^2 .

It is a cyclic number.

It is not a de Polignac number, because 1688213 - 2²⁰ = 639637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1688243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844106 + 844107.

It is an arithmetic number, because the mean of its divisors is an integer number (844107).

2^1688213 is an apocalyptic number.

It is an amenable number.

1688213 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688213 is an equidigital number, since it uses as much as digits as its factorization.

1688213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2304, while the sum is 29.

The square root of 1688213 is about 1299.3125105224. The cubic root of 1688213 is about 119.0718441951.

The spelling of 1688213 in words is "one million, six hundred eighty-eight thousand, two hundred thirteen".