220646891 has 2 divisors, whose sum is σ = 220646892. Its totient is φ = 220646890.

The previous prime is 220646861. The next prime is 220646957. The reversal of 220646891 is 198646022.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 220646891 - 2¹⁴ = 220630507 is a prime.

It is not a weakly prime, because it can be changed into another prime (220646801) 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, 110323445 + 110323446.

It is an arithmetic number, because the mean of its divisors is an integer number (110323446).

Almost surely, 2^220646891 is an apocalyptic number.

220646891 is a deficient number, since it is larger than the sum of its proper divisors (1).

220646891 is an equidigital number, since it uses as much as digits as its factorization.

220646891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 38.

The square root of 220646891 is about 14854.1876587042. The cubic root of 220646891 is about 604.2721853738.

The spelling of 220646891 in words is "two hundred twenty million, six hundred forty-six thousand, eight hundred ninety-one".