638298516065 has 16 divisors (see below), whose sum is σ = 899039764992. Its totient is φ = 425860939584.

The previous prime is 638298516059. The next prime is 638298516067. The reversal of 638298516065 is 560615892836.

It is a cyclic number.

It is not a de Polignac number, because 638298516065 - 2³² = 634003548769 is a prime.

It is a super-2 number, since 2×638298516065² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 638298515995 and 638298516013.

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 15 ways as a sum of consecutive naturals, for example, 246446009 + ... + 246448598.

It is an arithmetic number, because the mean of its divisors is an integer number (56189985312).

Almost surely, 2^638298516065 is an apocalyptic number.

It is an amenable number.

638298516065 is a deficient number, since it is larger than the sum of its proper divisors (260741248927).

638298516065 is a wasteful number, since it uses less digits than its factorization.

638298516065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492894656.

The product of its (nonzero) digits is 18662400, while the sum is 59.

The spelling of 638298516065 in words is "six hundred thirty-eight billion, two hundred ninety-eight million, five hundred sixteen thousand, sixty-five".