18413720440 has 64 divisors (see below), whose sum is σ = 42678043200. Its totient is φ = 7144962048.

The previous prime is 18413720333. The next prime is 18413720449. The reversal of 18413720440 is 4402731481.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 18413720396 and 18413720405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18413720449) 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, 480301 + ... + 517219.

It is an arithmetic number, because the mean of its divisors is an integer number (666844425).

Almost surely, 2^18413720440 is an apocalyptic number.

18413720440 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 18413720440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21339021600).

18413720440 is an abundant number, since it is smaller than the sum of its proper divisors (24264322760).

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

18413720440 is a wasteful number, since it uses less digits than its factorization.

18413720440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37304 (or 37300 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 34.

The spelling of 18413720440 in words is "eighteen billion, four hundred thirteen million, seven hundred twenty thousand, four hundred forty".