634890321920 has 128 divisors (see below), whose sum is σ = 1589971373280. Its totient is φ = 242913116160.

The previous prime is 634890321899. The next prime is 634890322007. The reversal of 634890321920 is 29123098436.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 3684080 + ... + 3852560.

Almost surely, 2^634890321920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 634890321920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (794985686640).

634890321920 is an abundant number, since it is smaller than the sum of its proper divisors (955081051360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

634890321920 is an equidigital number, since it uses as much as digits as its factorization.

634890321920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168539 (or 168511 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 47.

The spelling of 634890321920 in words is "six hundred thirty-four billion, eight hundred ninety million, three hundred twenty-one thousand, nine hundred twenty".