638196658870 has 16 divisors (see below), whose sum is σ = 1148809063968. Its totient is φ = 255266424000.

The previous prime is 638196658819. The next prime is 638196658873. The reversal of 638196658870 is 78856691836.

It is a super-2 number, since 2×638196658870² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 638196658796 and 638196658805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638196658873) 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, 1309434 + ... + 1729453.

It is an arithmetic number, because the mean of its divisors is an integer number (71800566498).

Almost surely, 2^638196658870 is an apocalyptic number.

638196658870 is a deficient number, since it is larger than the sum of its proper divisors (510612405098).

638196658870 is a wasteful number, since it uses less digits than its factorization.

638196658870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3059895.

The product of its (nonzero) digits is 104509440, while the sum is 67.

The spelling of 638196658870 in words is "six hundred thirty-eight billion, one hundred ninety-six million, six hundred fifty-eight thousand, eight hundred seventy".