16072921 has 4 divisors (see below), whose sum is σ = 16293172. Its totient is φ = 15852672.

The previous prime is 16072913. The next prime is 16072933. The reversal of 16072921 is 12927061.

It is a happy number.

16072921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7778521 + 8294400 = 2789^2 + 2880^2 .

It is a cyclic number.

It is not a de Polignac number, because 16072921 - 2³ = 16072913 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16072921.

It is not an unprimeable number, because it can be changed into a prime (16072961) 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, 110016 + ... + 110161.

It is an arithmetic number, because the mean of its divisors is an integer number (4073293).

Almost surely, 2^16072921 is an apocalyptic number.

It is an amenable number.

16072921 is a deficient number, since it is larger than the sum of its proper divisors (220251).

16072921 is an equidigital number, since it uses as much as digits as its factorization.

16072921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220250.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 16072921 is about 4009.1047629115. The cubic root of 16072921 is about 252.3664411469.

Adding to 16072921 its reverse (12927061), we get a palindrome (28999982).

The spelling of 16072921 in words is "sixteen million, seventy-two thousand, nine hundred twenty-one".