1022222221 has 2 divisors, whose sum is σ = 1022222222. Its totient is φ = 1022222220.

The previous prime is 1022222219. The next prime is 1022222231. The reversal of 1022222221 is 1222222201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 818589321 + 203632900 = 28611^2 + 14270^2 .

It is a cyclic number.

It is not a de Polignac number, because 1022222221 - 2¹ = 1022222219 is a prime.

Together with 1022222219, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1022222195 and 1022222204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1022222231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 511111110 + 511111111.

It is an arithmetic number, because the mean of its divisors is an integer number (511111111).

Almost surely, 2^1022222221 is an apocalyptic number.

It is an amenable number.

1022222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1022222221 is an equidigital number, since it uses as much as digits as its factorization.

1022222221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 1022222221 is about 31972.2101363043. The cubic root of 1022222221 is about 1007.3532048501.

Adding to 1022222221 its reverse (1222222201), we get a palindrome (2244444422).

The spelling of 1022222221 in words is "one billion, twenty-two million, two hundred twenty-two thousand, two hundred twenty-one".