16328621 has 4 divisors (see below), whose sum is σ = 16364352. Its totient is φ = 16292892.

The previous prime is 16328617. The next prime is 16328633. The reversal of 16328621 is 12682361.

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: 12682361 = 23 ⋅551407.

It is a cyclic number.

It is not a de Polignac number, because 16328621 - 2² = 16328617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16328671) 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, 17171 + ... + 18096.

It is an arithmetic number, because the mean of its divisors is an integer number (4091088).

Almost surely, 2^16328621 is an apocalyptic number.

It is an amenable number.

16328621 is a deficient number, since it is larger than the sum of its proper divisors (35731).

16328621 is an equidigital number, since it uses as much as digits as its factorization.

16328621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35730.

The product of its digits is 3456, while the sum is 29.

The square root of 16328621 is about 4040.8688422170. The cubic root of 16328621 is about 253.6976842167.

The spelling of 16328621 in words is "sixteen million, three hundred twenty-eight thousand, six hundred twenty-one".