15221144 has 8 divisors (see below), whose sum is σ = 28539660. Its totient is φ = 7610568.

The previous prime is 15221099. The next prime is 15221149. The reversal of 15221144 is 44112251.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15221149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 951314 + ... + 951329.

Almost surely, 2^15221144 is an apocalyptic number.

It is an amenable number.

15221144 is a deficient number, since it is larger than the sum of its proper divisors (13318516).

15221144 is a wasteful number, since it uses less digits than its factorization.

15221144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1902649 (or 1902645 counting only the distinct ones).

The product of its digits is 320, while the sum is 20.

The square root of 15221144 is about 3901.4284563478. The cubic root of 15221144 is about 247.8272730674.

Adding to 15221144 its reverse (44112251), we get a palindrome (59333395).

The spelling of 15221144 in words is "fifteen million, two hundred twenty-one thousand, one hundred forty-four".