638660112566 has 32 divisors (see below), whose sum is σ = 1095820876800. Its totient is φ = 273467871936.

The previous prime is 638660112509. The next prime is 638660112577. The reversal of 638660112566 is 665211066836.

It is a super-2 number, since 2×638660112566² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109188410 + ... + 109194258.

It is an arithmetic number, because the mean of its divisors is an integer number (34244402400).

Almost surely, 2^638660112566 is an apocalyptic number.

638660112566 is a deficient number, since it is larger than the sum of its proper divisors (457160764234).

638660112566 is a wasteful number, since it uses less digits than its factorization.

638660112566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11468.

The product of its (nonzero) digits is 1866240, while the sum is 50.

The spelling of 638660112566 in words is "six hundred thirty-eight billion, six hundred sixty million, one hundred twelve thousand, five hundred sixty-six".