16453021 has 4 divisors (see below), whose sum is σ = 17718652. Its totient is φ = 15187392.

The previous prime is 16452983. The next prime is 16453037. The reversal of 16453021 is 12035461.

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 9765625 + 6687396 = 3125^2 + 2586^2 .

It is a cyclic number.

It is not a de Polignac number, because 16453021 - 2¹³ = 16444829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16452983 and 16453001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16453061) 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, 632796 + ... + 632821.

It is an arithmetic number, because the mean of its divisors is an integer number (4429663).

Almost surely, 2^16453021 is an apocalyptic number.

It is an amenable number.

16453021 is a deficient number, since it is larger than the sum of its proper divisors (1265631).

16453021 is a wasteful number, since it uses less digits than its factorization.

16453021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1265630.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 16453021 is about 4056.2323651389. The cubic root of 16453021 is about 254.3403223298.

Adding to 16453021 its reverse (12035461), we get a palindrome (28488482).

The spelling of 16453021 in words is "sixteen million, four hundred fifty-three thousand, twenty-one".