16621444 has 24 divisors (see below), whose sum is σ = 35199360. Its totient is φ = 6704256.

The previous prime is 16621417. The next prime is 16621453. The reversal of 16621444 is 44412661.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16984 + ... + 17935.

It is an arithmetic number, because the mean of its divisors is an integer number (1466640).

Almost surely, 2^16621444 is an apocalyptic number.

16621444 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

16621444 is an abundant number, since it is smaller than the sum of its proper divisors (18577916).

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

16621444 is a wasteful number, since it uses less digits than its factorization.

16621444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34947 (or 34945 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 16621444 is about 4076.9405195563. The cubic root of 16621444 is about 255.2052378193.

The spelling of 16621444 in words is "sixteen million, six hundred twenty-one thousand, four hundred forty-four".