16321644 has 18 divisors (see below), whose sum is σ = 41257580. Its totient is φ = 5440536.

The previous prime is 16321633. The next prime is 16321667. The reversal of 16321644 is 44612361.

16321644 is a `hidden beast` number, since 16 + 3 + 2 + 1 + 644 = 666.

16321644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (18).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 226654 + ... + 226725.

Almost surely, 2^16321644 is an apocalyptic number.

It is an amenable number.

16321644 is an abundant number, since it is smaller than the sum of its proper divisors (24935936).

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

16321644 is a wasteful number, since it uses less digits than its factorization.

16321644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453389 (or 453384 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 16321644 is about 4040.0054455409. The cubic root of 16321644 is about 253.6615452002.

The spelling of 16321644 in words is "sixteen million, three hundred twenty-one thousand, six hundred forty-four".