634649 has 2 divisors, whose sum is σ = 634650. Its totient is φ = 634648.

The previous prime is 634643. The next prime is 634651. The reversal of 634649 is 946436.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 399424 + 235225 = 632^2 + 485^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-634649 is a prime.

It is a Sophie Germain prime.

Together with 634651, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (634643) 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, 317324 + 317325.

It is an arithmetic number, because the mean of its divisors is an integer number (317325).

2⁶³⁴⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

634649 is a deficient number, since it is larger than the sum of its proper divisors (1).

634649 is an equidigital number, since it uses as much as digits as its factorization.

634649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 32.

The square root of 634649 is about 796.6486050951. The cubic root of 634649 is about 85.9365405292.

The spelling of 634649 in words is "six hundred thirty-four thousand, six hundred forty-nine".