16009021 has 8 divisors (see below), whose sum is σ = 18641664. Its totient is φ = 13462800.

The previous prime is 16008991. The next prime is 16009033. The reversal of 16009021 is 12090061.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16009021 - 2¹¹ = 16006973 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 16009021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16009061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21205 + ... + 21946.

It is an arithmetic number, because the mean of its divisors is an integer number (2330208).

Almost surely, 2^16009021 is an apocalyptic number.

It is an amenable number.

16009021 is a deficient number, since it is larger than the sum of its proper divisors (2632643).

16009021 is an equidigital number, since it uses as much as digits as its factorization.

16009021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43211.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 16009021 is about 4001.1274661025. The cubic root of 16009021 is about 252.0315583640.

Adding to 16009021 its reverse (12090061), we get a palindrome (28099082).

The spelling of 16009021 in words is "sixteen million, nine thousand, twenty-one".