15505225 has 12 divisors (see below), whose sum is σ = 19284480. Its totient is φ = 12366800.

The previous prime is 15505219. The next prime is 15505229. The reversal of 15505225 is 52250551.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-15505225 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 15505225.

It is not an unprimeable number, because it can be changed into a prime (15505229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10056 + ... + 11494.

It is an arithmetic number, because the mean of its divisors is an integer number (1607040).

Almost surely, 2^15505225 is an apocalyptic number.

It is an amenable number.

15505225 is a deficient number, since it is larger than the sum of its proper divisors (3779255).

15505225 is a wasteful number, since it uses less digits than its factorization.

15505225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1880 (or 1875 counting only the distinct ones).

The product of its (nonzero) digits is 2500, while the sum is 25.

The square root of 15505225 is about 3937.6674567566. The cubic root of 15505225 is about 249.3595607513.

Adding to 15505225 its reverse (52250551), we get a palindrome (67755776).

The spelling of 15505225 in words is "fifteen million, five hundred five thousand, two hundred twenty-five".