18661735645632 has 336 divisors, whose sum is σ = 57839780444160. Its totient is φ = 5733694439424.

The previous prime is 18661735645627. The next prime is 18661735645633. The reversal of 18661735645632 is 23654653716681.

18661735645632 is a `hidden beast` number, since 1 + 8 + 6 + 6 + 1 + 7 + 3 + 5 + 64 + 563 + 2 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 18661735645632.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18661735645633) 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 47 ways as a sum of consecutive naturals, for example, 120864993 + ... + 121019295.

Almost surely, 2^{18661735645632} is an apocalyptic number.

18661735645632 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18661735645632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28919890222080).

18661735645632 is an abundant number, since it is smaller than the sum of its proper divisors (39178044798528).

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

18661735645632 is a wasteful number, since it uses less digits than its factorization.

18661735645632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154640 (or 154627 counting only the distinct ones).

The product of its digits is 130636800, while the sum is 63.

The spelling of 18661735645632 in words is "eighteen trillion, six hundred sixty-one billion, seven hundred thirty-five million, six hundred forty-five thousand, six hundred thirty-two".