16033921 has 4 divisors (see below), whose sum is σ = 16731072. Its totient is φ = 15336772.

The previous prime is 16033903. The next prime is 16033933. The reversal of 16033921 is 12933061.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12933061 = 23 ⋅562307.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16033921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16033951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 348541 + ... + 348586.

It is an arithmetic number, because the mean of its divisors is an integer number (4182768).

Almost surely, 2^16033921 is an apocalyptic number.

It is an amenable number.

16033921 is a deficient number, since it is larger than the sum of its proper divisors (697151).

16033921 is an equidigital number, since it uses as much as digits as its factorization.

16033921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697150.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 16033921 is about 4004.2378800466. The cubic root of 16033921 is about 252.1621583756.

Adding to 16033921 its reverse (12933061), we get a palindrome (28966982).

The spelling of 16033921 in words is "sixteen million, thirty-three thousand, nine hundred twenty-one".