4644181786638 has 32 divisors (see below), whose sum is σ = 9768893663232. Its totient is φ = 1469856679200.

The previous prime is 4644181786637. The next prime is 4644181786649. The reversal of 4644181786638 is 8366871814464.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4644181786637) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 235544098 + ... + 235563813.

It is an arithmetic number, because the mean of its divisors is an integer number (305277926976).

Almost surely, 2^{4644181786638} is an apocalyptic number.

4644181786638 is an abundant number, since it is smaller than the sum of its proper divisors (5124711876594).

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

4644181786638 is a wasteful number, since it uses less digits than its factorization.

4644181786638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471108000.

The product of its digits is 148635648, while the sum is 66.

The spelling of 4644181786638 in words is "four trillion, six hundred forty-four billion, one hundred eighty-one million, seven hundred eighty-six thousand, six hundred thirty-eight".