638655634443 has 8 divisors (see below), whose sum is σ = 851944237056. Its totient is φ = 425568727400.

The previous prime is 638655634427. The next prime is 638655634457. The reversal of 638655634443 is 344436556836.

638655634443 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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 638655634443 - 2⁴ = 638655634427 is a prime.

It is not an unprimeable number, because it can be changed into a prime (638655624443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50416503 + ... + 50429168.

It is an arithmetic number, because the mean of its divisors is an integer number (106493029632).

Almost surely, 2^638655634443 is an apocalyptic number.

638655634443 is a deficient number, since it is larger than the sum of its proper divisors (213288602613).

638655634443 is a wasteful number, since it uses less digits than its factorization.

638655634443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100847785.

The product of its digits is 74649600, while the sum is 57.

The spelling of 638655634443 in words is "six hundred thirty-eight billion, six hundred fifty-five million, six hundred thirty-four thousand, four hundred forty-three".