638298516066 has 8 divisors (see below), whose sum is σ = 1276597032144. Its totient is φ = 212766172020.

The previous prime is 638298516059. The next prime is 638298516067. The reversal of 638298516066 is 660615892836.

It is a happy number.

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

638298516066 is an admirable number.

It is a super-2 number, since 2×638298516066² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (638298516067) 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, 53191543000 + ... + 53191543011.

It is an arithmetic number, because the mean of its divisors is an integer number (159574629018).

Almost surely, 2^638298516066 is an apocalyptic number.

638298516066 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

638298516066 is a wasteful number, since it uses less digits than its factorization.

638298516066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106383086016.

The product of its (nonzero) digits is 22394880, while the sum is 60.

The spelling of 638298516066 in words is "six hundred thirty-eight billion, two hundred ninety-eight million, five hundred sixteen thousand, sixty-six".