18278681552640 has 432 divisors, whose sum is σ = 66980537402688. Its totient is φ = 4586353065984.

The previous prime is 18278681552609. The next prime is 18278681552669. The reversal of 18278681552640 is 4625518687281.

18278681552640 is a `hidden beast` number, since 1 + 8 + 2 + 7 + 8 + 68 + 1 + 5 + 526 + 40 = 666.

It is a super-2 number, since 2×18278681552640² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 884598949 + ... + 884619611.

It is an arithmetic number, because the mean of its divisors is an integer number (155047540284).

Almost surely, 2^{18278681552640} is an apocalyptic number.

18278681552640 is a gapful number since it is divisible by the number (10) 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 18278681552640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33490268701344).

18278681552640 is an abundant number, since it is smaller than the sum of its proper divisors (48701855850048).

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

18278681552640 is a wasteful number, since it uses less digits than its factorization.

18278681552640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25224 (or 25207 counting only the distinct ones).

The product of its (nonzero) digits is 51609600, while the sum is 63.

The spelling of 18278681552640 in words is "eighteen trillion, two hundred seventy-eight billion, six hundred eighty-one million, five hundred fifty-two thousand, six hundred forty".