15420224 has 28 divisors (see below), whose sum is σ = 32401764. Its totient is φ = 7256064.

The previous prime is 15420221. The next prime is 15420253. The reversal of 15420224 is 42202451.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12730624 + 2689600 = 3568^2 + 1640^2 .

It is a junction number, because it is equal to n+sod(n) for n = 15420196 and 15420205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15420221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5999 + ... + 8174.

Almost surely, 2^15420224 is an apocalyptic number.

It is an amenable number.

15420224 is an abundant number, since it is smaller than the sum of its proper divisors (16981540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15420224 is a wasteful number, since it uses less digits than its factorization.

15420224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14202 (or 14192 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 15420224 is about 3926.8593048389. The cubic root of 15420224 is about 248.9030552216.

Adding to 15420224 its reverse (42202451), we get a palindrome (57622675).

The spelling of 15420224 in words is "fifteen million, four hundred twenty thousand, two hundred twenty-four".