634536389 has 2 divisors, whose sum is σ = 634536390. Its totient is φ = 634536388.

The previous prime is 634536349. The next prime is 634536391. The reversal of 634536389 is 983635436.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 634536100 + 289 = 25190^2 + 17^2 .

It is a cyclic number.

It is not a de Polignac number, because 634536389 - 2¹⁶ = 634470853 is a prime.

Together with 634536391, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (634536349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317268194 + 317268195.

It is an arithmetic number, because the mean of its divisors is an integer number (317268195).

Almost surely, 2^634536389 is an apocalyptic number.

It is an amenable number.

634536389 is a deficient number, since it is larger than the sum of its proper divisors (1).

634536389 is an equidigital number, since it uses as much as digits as its factorization.

634536389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1399680, while the sum is 47.

The square root of 634536389 is about 25190.0057364027. The cubic root of 634536389 is about 859.3145741914.

The spelling of 634536389 in words is "six hundred thirty-four million, five hundred thirty-six thousand, three hundred eighty-nine".