16381440 has 200 divisors, whose sum is σ = 59415840. Its totient is φ = 4313088.

The previous prime is 16381397. The next prime is 16381447. The reversal of 16381440 is 4418361.

16381440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16381447) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 207321 + ... + 207399.

Almost surely, 2^16381440 is an apocalyptic number.

16381440 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 16381440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29707920).

16381440 is an abundant number, since it is smaller than the sum of its proper divisors (43034400).

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

16381440 is an frugal number, since it uses more digits than its factorization.

16381440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 16381440 is about 4047.3991648959. The cubic root of 16381440 is about 253.9709392838.

The spelling of 16381440 in words is "sixteen million, three hundred eighty-one thousand, four hundred forty".