1338670638 has 80 divisors (see below), whose sum is σ = 3093456960. Its totient is φ = 432454464.

The previous prime is 1338670637. The next prime is 1338670657. The reversal of 1338670638 is 8360768331.

1338670638 is a `hidden beast` number, since 1 + 3 + 3 + 8 + 6 + 7 + 0 + 638 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1338670593 and 1338670602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1338670637) 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 39 ways as a sum of consecutive naturals, for example, 829120 + ... + 830732.

It is an arithmetic number, because the mean of its divisors is an integer number (38668212).

Almost surely, 2^1338670638 is an apocalyptic number.

1338670638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1338670638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1546728480).

1338670638 is an abundant number, since it is smaller than the sum of its proper divisors (1754786322).

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

1338670638 is a wasteful number, since it uses less digits than its factorization.

1338670638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783 (or 1774 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 1338670638 is about 36587.8482286127. The cubic root of 1338670638 is about 1102.1090770080.

The spelling of 1338670638 in words is "one billion, three hundred thirty-eight million, six hundred seventy thousand, six hundred thirty-eight".