16221125 has 8 divisors (see below), whose sum is σ = 20244120. Its totient is φ = 12976800.

The previous prime is 16221119. The next prime is 16221137. The reversal of 16221125 is 52112261.

It can be written as a sum of positive squares in 4 ways, for example, as 332929 + 15888196 = 577^2 + 3986^2 .

It is not a de Polignac number, because 16221125 - 2⁴ = 16221109 is a prime.

It is a Curzon number.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 16221097 and 16221106.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64760 + ... + 65009.

It is an arithmetic number, because the mean of its divisors is an integer number (2530515).

Almost surely, 2^16221125 is an apocalyptic number.

It is an amenable number.

16221125 is a deficient number, since it is larger than the sum of its proper divisors (4022995).

16221125 is an equidigital number, since it uses as much as digits as its factorization.

16221125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129784 (or 129774 counting only the distinct ones).

The product of its digits is 240, while the sum is 20.

The square root of 16221125 is about 4027.5457787591. The cubic root of 16221125 is about 253.1397364788.

Adding to 16221125 its reverse (52112261), we get a palindrome (68333386).

The spelling of 16221125 in words is "sixteen million, two hundred twenty-one thousand, one hundred twenty-five".