16511225 has 6 divisors (see below), whose sum is σ = 20473950. Its totient is φ = 13208960.

The previous prime is 16511203. The next prime is 16511227. The reversal of 16511225 is 52211561.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 3341584 + 13169641 = 1828^2 + 3629^2 .

It is not a de Polignac number, because 16511225 - 2⁸ = 16510969 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16511225.

It is not an unprimeable number, because it can be changed into a prime (16511227) 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 5 ways as a sum of consecutive naturals, for example, 330200 + ... + 330249.

It is an arithmetic number, because the mean of its divisors is an integer number (3412325).

Almost surely, 2^16511225 is an apocalyptic number.

It is an amenable number.

16511225 is a deficient number, since it is larger than the sum of its proper divisors (3962725).

16511225 is an equidigital number, since it uses as much as digits as its factorization.

16511225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660459 (or 660454 counting only the distinct ones).

The product of its digits is 600, while the sum is 23.

The square root of 16511225 is about 4063.4006693901. The cubic root of 16511225 is about 254.6398864033.

Adding to 16511225 its reverse (52211561), we get a palindrome (68722786).

It can be divided in two parts, 16 and 511225, that multiplied together give a square (8179600 = 2860²).

The spelling of 16511225 in words is "sixteen million, five hundred eleven thousand, two hundred twenty-five".