16440000 has 140 divisors (see below), whose sum is σ = 54751224. Its totient is φ = 4352000.

The previous prime is 16439999. The next prime is 16440007. The reversal of 16440000 is 4461.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (16440007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 119932 + ... + 120068.

Almost surely, 2^16440000 is an apocalyptic number.

16440000 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 16440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27375612).

16440000 is an abundant number, since it is smaller than the sum of its proper divisors (38311224).

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

16440000 is an equidigital number, since it uses as much as digits as its factorization.

16440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 16440000 is about 4054.6269865427. The cubic root of 16440000 is about 254.2732092371.

Adding to 16440000 its reverse (4461), we get a palindrome (16444461).

The spelling of 16440000 in words is "sixteen million, four hundred forty thousand".