221430775 has 24 divisors (see below), whose sum is σ = 289222560. Its totient is φ = 167840640.

The previous prime is 221430757. The next prime is 221430787. The reversal of 221430775 is 577034122.

It is not a de Polignac number, because 221430775 - 2¹³ = 221422583 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 23 ways as a sum of consecutive naturals, for example, 60909 + ... + 64441.

It is an arithmetic number, because the mean of its divisors is an integer number (12050940).

Almost surely, 2^221430775 is an apocalyptic number.

221430775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

221430775 is a deficient number, since it is larger than the sum of its proper divisors (67791785).

221430775 is a wasteful number, since it uses less digits than its factorization.

221430775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3675 (or 3670 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 31.

The square root of 221430775 is about 14880.5502250421. The cubic root of 221430775 is about 604.9869313936.

Adding to 221430775 its reverse (577034122), we get a palindrome (798464897).

The spelling of 221430775 in words is "two hundred twenty-one million, four hundred thirty thousand, seven hundred seventy-five".