221042281 has 2 divisors, whose sum is σ = 221042282. Its totient is φ = 221042280.

The previous prime is 221042221. The next prime is 221042287. The reversal of 221042281 is 182240122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209786256 + 11256025 = 14484^2 + 3355^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221042281 is a prime.

It is a super-2 number, since 2×221042281² = 97719379979365922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221042287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110521140 + 110521141.

It is an arithmetic number, because the mean of its divisors is an integer number (110521141).

Almost surely, 2^221042281 is an apocalyptic number.

It is an amenable number.

221042281 is a deficient number, since it is larger than the sum of its proper divisors (1).

221042281 is an equidigital number, since it uses as much as digits as its factorization.

221042281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 221042281 is about 14867.4907432290. The cubic root of 221042281 is about 604.6329134837.

The spelling of 221042281 in words is "two hundred twenty-one million, forty-two thousand, two hundred eighty-one".