634467778559 has 4 divisors (see below), whose sum is σ = 635729146416. Its totient is φ = 633206410704.

The previous prime is 634467778543. The next prime is 634467778589. The reversal of 634467778559 is 955877764436.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 634467778559 - 2⁴ = 634467778543 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 634467778492 and 634467778501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634467778519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 630683174 + ... + 630684179.

It is an arithmetic number, because the mean of its divisors is an integer number (158932286604).

Almost surely, 2^634467778559 is an apocalyptic number.

634467778559 is a deficient number, since it is larger than the sum of its proper divisors (1261367857).

634467778559 is a wasteful number, since it uses less digits than its factorization.

634467778559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1261367856.

The product of its digits is 1066867200, while the sum is 71.

The spelling of 634467778559 in words is "six hundred thirty-four billion, four hundred sixty-seven million, seven hundred seventy-eight thousand, five hundred fifty-nine".