16624121 has 4 divisors (see below), whose sum is σ = 16660644. Its totient is φ = 16587600.

The previous prime is 16624109. The next prime is 16624129. The reversal of 16624121 is 12142661.

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 4818025 + 11806096 = 2195^2 + 3436^2 .

It is a cyclic number.

It is not a de Polignac number, because 16624121 - 2¹⁸ = 16361977 is a prime.

It is a super-2 number, since 2×16624121² = 552722798045282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16624129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17570 + ... + 18491.

It is an arithmetic number, because the mean of its divisors is an integer number (4165161).

Almost surely, 2^16624121 is an apocalyptic number.

It is an amenable number.

16624121 is a deficient number, since it is larger than the sum of its proper divisors (36523).

16624121 is an equidigital number, since it uses as much as digits as its factorization.

16624121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36522.

The product of its digits is 576, while the sum is 23.

The square root of 16624121 is about 4077.2688162543. The cubic root of 16624121 is about 255.2189379476.

Adding to 16624121 its reverse (12142661), we get a palindrome (28766782).

The spelling of 16624121 in words is "sixteen million, six hundred twenty-four thousand, one hundred twenty-one".