1242643 has 2 divisors, whose sum is σ = 1242644. Its totient is φ = 1242642.

The previous prime is 1242641. The next prime is 1242739. The reversal of 1242643 is 3462421.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1242643 - 2¹ = 1242641 is a prime.

Together with 1242641, it forms a pair of twin primes.

It is a plaindrome in base 13.

It is not a weakly prime, because it can be changed into another prime (1242641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621321 + 621322.

It is an arithmetic number, because the mean of its divisors is an integer number (621322).

2^1242643 is an apocalyptic number.

1242643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242643 is an equidigital number, since it uses as much as digits as its factorization.

1242643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 22.

The square root of 1242643 is about 1114.7389829014. The cubic root of 1242643 is about 107.5099828479.

The spelling of 1242643 in words is "one million, two hundred forty-two thousand, six hundred forty-three".