16440621 has 4 divisors (see below), whose sum is σ = 21920832. Its totient is φ = 10960412.

The previous prime is 16440601. The next prime is 16440623. The reversal of 16440621 is 12604461.

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.

It is a cyclic number.

It is not a de Polignac number, because 16440621 - 2¹¹ = 16438573 is a prime.

It is a super-3 number, since 3×16440621³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16440591 and 16440600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16440623) 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, 2740101 + ... + 2740106.

It is an arithmetic number, because the mean of its divisors is an integer number (5480208).

Almost surely, 2^16440621 is an apocalyptic number.

It is an amenable number.

16440621 is a deficient number, since it is larger than the sum of its proper divisors (5480211).

16440621 is an equidigital number, since it uses as much as digits as its factorization.

16440621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5480210.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 16440621 is about 4054.7035649971. The cubic root of 16440621 is about 254.2764108120.

The spelling of 16440621 in words is "sixteen million, four hundred forty thousand, six hundred twenty-one".