634643 has 2 divisors, whose sum is σ = 634644. Its totient is φ = 634642.

The previous prime is 634609. The next prime is 634649. The reversal of 634643 is 346436.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-634643 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (634649) 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, 317321 + 317322.

It is an arithmetic number, because the mean of its divisors is an integer number (317322).

2⁶³⁴⁶⁴³ is an apocalyptic number.

634643 is a deficient number, since it is larger than the sum of its proper divisors (1).

634643 is an equidigital number, since it uses as much as digits as its factorization.

634643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 26.

The square root of 634643 is about 796.6448393105. The cubic root of 634643 is about 85.9362697124.

The spelling of 634643 in words is "six hundred thirty-four thousand, six hundred forty-three".