12638257644 has 24 divisors (see below), whose sum is σ = 29750238000. Its totient is φ = 4175471104.

The previous prime is 12638257633. The next prime is 12638257669. The reversal of 12638257644 is 44675283621.

It is a super-3 number, since 3×12638257644³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 12638257593 and 12638257602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4658769 + ... + 4661480.

It is an arithmetic number, because the mean of its divisors is an integer number (1239593250).

Almost surely, 2^12638257644 is an apocalyptic number.

It is an amenable number.

12638257644 is an abundant number, since it is smaller than the sum of its proper divisors (17111980356).

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

12638257644 is a wasteful number, since it uses less digits than its factorization.

12638257644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9320369 (or 9320367 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 48.

The spelling of 12638257644 in words is "twelve billion, six hundred thirty-eight million, two hundred fifty-seven thousand, six hundred forty-four".