638820063257 has 8 divisors (see below), whose sum is σ = 667153632384. Its totient is φ = 610533059488.

The previous prime is 638820063253. The next prime is 638820063269. The reversal of 638820063257 is 752360028836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 638820063257 - 2² = 638820063253 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638820063253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11613293 + ... + 11668170.

It is an arithmetic number, because the mean of its divisors is an integer number (83394204048).

Almost surely, 2^638820063257 is an apocalyptic number.

It is an amenable number.

638820063257 is a deficient number, since it is larger than the sum of its proper divisors (28333569127).

638820063257 is a wasteful number, since it uses less digits than its factorization.

638820063257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23282679.

The product of its (nonzero) digits is 2903040, while the sum is 50.

The spelling of 638820063257 in words is "six hundred thirty-eight billion, eight hundred twenty million, sixty-three thousand, two hundred fifty-seven".