4221551 has 2 divisors, whose sum is σ = 4221552. Its totient is φ = 4221550.

The previous prime is 4221541. The next prime is 4221563. The reversal of 4221551 is 1551224.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4221551 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4221521) 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 as a sum of consecutive naturals, namely, 2110775 + 2110776.

It is an arithmetic number, because the mean of its divisors is an integer number (2110776).

Almost surely, 2^4221551 is an apocalyptic number.

4221551 is a deficient number, since it is larger than the sum of its proper divisors (1).

4221551 is an equidigital number, since it uses as much as digits as its factorization.

4221551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 400, while the sum is 20.

The square root of 4221551 is about 2054.6413312303. The cubic root of 4221551 is about 161.6183542651.

Adding to 4221551 its reverse (1551224), we get a palindrome (5772775).

The spelling of 4221551 in words is "four million, two hundred twenty-one thousand, five hundred fifty-one".