18231696421380 has 144 divisors (see below), whose sum is σ = 59568985847280. Its totient is φ = 4486889604096.

The previous prime is 18231696421349. The next prime is 18231696421381. The reversal of 18231696421380 is 8312469613281.

It is a happy number.

18231696421380 is a `hidden beast` number, since 1 + 8 + 23 + 169 + 6 + 421 + 38 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 5639361570756 + 12592334850624 = 2374734^2 + 3548568^2 .

It is a super-2 number, since 2×18231696421380² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18231696421381) 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, 10753506 + ... + 12332934.

Almost surely, 2^{18231696421380} is an apocalyptic number.

18231696421380 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 18231696421380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29784492923640).

18231696421380 is an abundant number, since it is smaller than the sum of its proper divisors (41337289425900).

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

18231696421380 is a wasteful number, since it uses less digits than its factorization.

18231696421380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1584390 (or 1584385 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The spelling of 18231696421380 in words is "eighteen trillion, two hundred thirty-one billion, six hundred ninety-six million, four hundred twenty-one thousand, three hundred eighty".