15227221 has 2 divisors, whose sum is σ = 15227222. Its totient is φ = 15227220.

The previous prime is 15227213. The next prime is 15227243. The reversal of 15227221 is 12272251.

15227221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (15227243) can be obtained adding 15227221 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14546596 + 680625 = 3814^2 + 825^2 .

It is a cyclic number.

It is not a de Polignac number, because 15227221 - 2³ = 15227213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 15227192 and 15227201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15227021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7613610 + 7613611.

It is an arithmetic number, because the mean of its divisors is an integer number (7613611).

Almost surely, 2^15227221 is an apocalyptic number.

It is an amenable number.

15227221 is a deficient number, since it is larger than the sum of its proper divisors (1).

15227221 is an equidigital number, since it uses as much as digits as its factorization.

15227221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 560, while the sum is 22.

The square root of 15227221 is about 3902.2071959341. The cubic root of 15227221 is about 247.8602501322.

Adding to 15227221 its reverse (12272251), we get a palindrome (27499472).

The spelling of 15227221 in words is "fifteen million, two hundred twenty-seven thousand, two hundred twenty-one".