1239643 has 2 divisors, whose sum is σ = 1239644. Its totient is φ = 1239642.

The previous prime is 1239619. The next prime is 1239661. The reversal of 1239643 is 3469321.

It is a strong prime.

It is an emirp because it is prime and its reverse (3469321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1239643 - 2¹⁷ = 1108571 is a prime.

It is not a weakly prime, because it can be changed into another prime (1239443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 619821 + 619822.

It is an arithmetic number, because the mean of its divisors is an integer number (619822).

2^1239643 is an apocalyptic number.

1239643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1239643 is an equidigital number, since it uses as much as digits as its factorization.

1239643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 28.

The square root of 1239643 is about 1113.3925632947. The cubic root of 1239643 is about 107.4233959390.

It can be divided in two parts, 12396 and 43, that multiplied together give a triangular number (533028 = T₁₀₃₂).

The spelling of 1239643 in words is "one million, two hundred thirty-nine thousand, six hundred forty-three".