18244539220 has 12 divisors (see below), whose sum is σ = 38313532404. Its totient is φ = 7297815680.

The previous prime is 18244539149. The next prime is 18244539221. The reversal of 18244539220 is 2293544281.

It can be written as a sum of positive squares in 2 ways, for example, as 5414899396 + 12829639824 = 73586^2 + 113268^2 .

It is a super-2 number, since 2×18244539220² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18244539221) 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 3 ways as a sum of consecutive naturals, for example, 456113461 + ... + 456113500.

It is an arithmetic number, because the mean of its divisors is an integer number (3192794367).

Almost surely, 2^18244539220 is an apocalyptic number.

18244539220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18244539220 is an abundant number, since it is smaller than the sum of its proper divisors (20068993184).

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

18244539220 is a wasteful number, since it uses less digits than its factorization.

18244539220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912226970 (or 912226968 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 40.

The spelling of 18244539220 in words is "eighteen billion, two hundred forty-four million, five hundred thirty-nine thousand, two hundred twenty".