221020279 has 2 divisors, whose sum is σ = 221020280. Its totient is φ = 221020278.

The previous prime is 221020237. The next prime is 221020321. The reversal of 221020279 is 972020122.

It is a balanced prime because it is at equal distance from previous prime (221020237) and next prime (221020321).

It is a cyclic number.

It is not a de Polignac number, because 221020279 - 2⁹ = 221019767 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221020379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510139 + 110510140.

It is an arithmetic number, because the mean of its divisors is an integer number (110510140).

Almost surely, 2^221020279 is an apocalyptic number.

221020279 is a deficient number, since it is larger than the sum of its proper divisors (1).

221020279 is an equidigital number, since it uses as much as digits as its factorization.

221020279 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 221020279 is about 14866.7507882523. The cubic root of 221020279 is about 604.6128515983.

The spelling of 221020279 in words is "two hundred twenty-one million, twenty thousand, two hundred seventy-nine".