634242125035551 has 4 divisors (see below), whose sum is σ = 845656166714072. Its totient is φ = 422828083357032.

The previous prime is 634242125035529. The next prime is 634242125035567. The reversal of 634242125035551 is 155530521242436.

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

It is not a de Polignac number, because 634242125035551 - 2³¹ = 634239977551903 is a prime.

It is a super-2 number, since 2×634242125035551² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 634242125035551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634242125035151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105707020839256 + ... + 105707020839261.

It is an arithmetic number, because the mean of its divisors is an integer number (211414041678518).

Almost surely, 2^{634242125035551} is an apocalyptic number.

634242125035551 is a deficient number, since it is larger than the sum of its proper divisors (211414041678521).

634242125035551 is a wasteful number, since it uses less digits than its factorization.

634242125035551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211414041678520.

The product of its (nonzero) digits is 4320000, while the sum is 48.

Adding to 634242125035551 its reverse (155530521242436), we get a palindrome (789772646277987).

The spelling of 634242125035551 in words is "six hundred thirty-four trillion, two hundred forty-two billion, one hundred twenty-five million, thirty-five thousand, five hundred fifty-one".