18811453440 has 368 divisors, whose sum is σ = 67645726848. Its totient is φ = 4429185024.

The previous prime is 18811453433. The next prime is 18811453447. The reversal of 18811453440 is 4435411881.

It is an interprime number because it is at equal distance from previous prime (18811453433) and next prime (18811453447).

It is a tau number, because it is divible by the number of its divisors (368).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18811453447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 817889269 + ... + 817889291.

Almost surely, 2^18811453440 is an apocalyptic number.

18811453440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18811453440 is a droll number since its even prime factors and its odd prime factors have the same sum.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18811453440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33822863424).

18811453440 is an abundant number, since it is smaller than the sum of its proper divisors (48834273408).

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

18811453440 is an frugal number, since it uses more digits than its factorization.

18811453440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 39.

The spelling of 18811453440 in words is "eighteen billion, eight hundred eleven million, four hundred fifty-three thousand, four hundred forty".