221425517 has 2 divisors, whose sum is σ = 221425518. Its totient is φ = 221425516.

The previous prime is 221425511. The next prime is 221425549. The reversal of 221425517 is 715524122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 195832036 + 25593481 = 13994^2 + 5059^2 .

It is a cyclic number.

It is not a de Polignac number, because 221425517 - 2⁶ = 221425453 is a prime.

It is a Chen prime.

It is equal to p_12196721 and since 221425517 and 12196721 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221425517.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221425511) 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 as a sum of consecutive naturals, namely, 110712758 + 110712759.

It is an arithmetic number, because the mean of its divisors is an integer number (110712759).

Almost surely, 2^221425517 is an apocalyptic number.

It is an amenable number.

221425517 is a deficient number, since it is larger than the sum of its proper divisors (1).

221425517 is an equidigital number, since it uses as much as digits as its factorization.

221425517 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5600, while the sum is 29.

The square root of 221425517 is about 14880.3735504187. The cubic root of 221425517 is about 604.9821427692.

Adding to 221425517 its reverse (715524122), we get a palindrome (936949639).

The spelling of 221425517 in words is "two hundred twenty-one million, four hundred twenty-five thousand, five hundred seventeen".